The combination of elements that will be most likely to form an ionic compound is one where there is a large difference in electronegativity between the two atoms. This is because ionic bonds are formed when there is a transfer of electrons from one atom to another, resulting in the formation of cations and anions.
In general, metal atoms tend to have low electronegativities, while nonmetal atoms tend to have high electronegativities. Therefore, a combination of a metal and a nonmetal is most likely to form an ionic compound.
For example, sodium (Na) is a metal with low electronegativity, while chlorine (Cl) is a non-metal with high electronegativity. When sodium and chlorine react, sodium donates its outer electron to chlorine, forming the ionic compound sodium chloride (NaCl).
Other examples of metal-nonmetal combinations that are likely to form ionic compounds include magnesium (Mg) and oxygen (O) (forming MgO), and aluminium (Al) and fluorine (F) (forming AlF3).
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a chemistry graduate student is given of a pyridine solution. pyridine is a weak base with . what mass of should the student dissolve in the solution to turn it into a buffer with ph ? you may assume that the volume of the solution doesn't change when the is dissolved in it. be sure your answer has a unit symbol, and round it to significant digits.
The mass of C₅H₅NHCl , the student should be dissolve in the solution to turn it into a buffer with ph = 5.64 is equals to the 31.45g.
We have a pyridine solution, which is a weak base solution. For a weak base,
the ionization constant, kb = 1.7 × 10⁻⁹
Buffer pH = 5.64
Volume of solution = 250 mL
Molarity of solution = 0.7 M
Using pH formula, pKb = - log ( 1.7 × 10⁻⁹)
= 8.77
For pH of equilibrium constant of water,
pKw = pKb + pKa
=> 14 = 8.77 + pKa
=> pKa = 5.23
Buffer pH formula = pKa + log( [[C₅H₅N] /[C₅H₅NHCl])
=> 5.64 = 5.23 + log( 0.7 M/[C₅H₅NHCl])
=> log(0.7 M/[C₅H₅NHCl]) = 5.64 - 5.23
=> log(0.7 M/[C₅H₅NHCl]) = 0.41
So, 0.7 M/[C₅H₅NHCl] = 10⁻⁰·⁴¹
=> [C₅H₅NHCl] = 10⁻⁰·⁴¹ × 0.7 M
Moles of [C₅H₅NHCl] = 250 mL× 10⁻⁰·⁴¹ × 0.7 mol [C₅H₅NHCl] / 1000 mL
= (0.7 ×10⁻⁰·⁴¹)/4
= 0.175 ×10⁻⁰·⁴¹ moles = 0.2723 moles.
Molar mass of C₅H₅NHCl = 115.5 g/mol
Mass of [C₅H₅NHCl] = 0.175 ×10⁻⁰·⁴¹ moles × 115.5 g [C₅H₅NHCl]/ 1 mol of [C₅H₅NHCl]
= 0.2723 × 115.5 g = 31.454 g
Hence, required mass is 31.45 g.
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Complete question:
a chemistry graduate student is given 250 ml of a 0.7 M pyridine solution C5H5N. pyridine is a weak base with Kb = 1.7 × 10-9. what mass of C5H5NHCl should the student dissolve in the solution to turn it into a buffer with ph= 5.64 ? you may assume that the volume of the solution doesn't change when the is dissolved in it. be sure your answer has a unit symbol, and round it to significant digits.
Express your answer as a balanced chemical equation.
Please find attached herewith the solutions for your questions.
To balance a chemical equation, you have to keep in mind these steps:
Write down the correct formulae of reactants and products.Find out which element has maximum number of atoms. Then balance that element on the other side.Now, balance other elements accordingly. For doing it easily, you can make two columns and do LHS and RHS.Verify that the number of atoms of each element is balanced in the final equation.Write the states of the compounds only if you know them.Hope it helps.
If you have any query, feel free to ask.
2 C2H6+7 O2⇒4 CO2+6 H2O is carbon balanced?
Answer:
To determine if the given chemical equation is carbon balanced, we need to count the number of carbon atoms in the reactants and compare it to the number of carbon atoms in the products.
Reactants:
2 C2H6 -> 4 carbon atoms
Products:
4 CO2 -> 4 carbon atoms
Since the number of carbon atoms on the reactant side is equal to the number of carbon atoms on the product side, we can conclude that the given chemical equation is carbon balanced.
solutions of each of the hypothetical acids in the following table are prepared with an initial concentration of 0.100 m. which of the four solutions will have the lowest ph and be most acidic? acid pka ha 4.00 hb 7.00 hc 10.00 hd 11.00
Solution d will have the lowest pH and be most acidic. The pH of a solution is inversely proportional to the strength of the acid, which means the stronger the acid, the lower the pH, and the more acidic the solution.
The strength of an acid is determined by its dissociation constant, Ka. A smaller Ka value means a weaker acid and a larger Ka value means a stronger acid. The pH of the four solutions will be calculated using the following equation: pH = pKa + log([A-]/[HA]), where [A-] and [HA] are the concentrations of the conjugate base and acid, respectively, and pKa is the dissociation constant of the acid.
Here, we have the following pKa values: acid pka ha 4.00 hb 7.00 hc 10.00 hd 11.00The strongest acid will have the smallest pKa value and the weakest acid will have the largest pKa value.
Therefore, the order of acidic strength is: d > c > b > a The lowest pH and the most acidic solution will be that which has the strongest acid. Since acid d has the lowest pKa value, it is the strongest acid, and its solution will have the lowest pH and be the most acidic.
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how many atoms of nitrogen, carbon, oxygen and hydrogen atoms are in 1.68 ×10⁴grams of urea
Urea's molecular formula is (NH₂)2CO. The Avogadro's number, or 6.022 10²³ atoms/mol, must be used to determine the number of atoms in a given amount of urea.
What percentage of NCO and H atoms are there in urea?Nowadays, urea molecules include a total of 8 atoms, of which 4 are in the H atom, 2 in the N atom, 1 in the C atom, and 1 in the O atom. In 5.6 g of urea, there are 2.247 1023 H atoms, 1.124 1023 N atoms, 0.562 10²³ C atoms, and 0.562 10²³ O atoms.
In how many atoms does urea consist?Carbon, nitrogen, oxygen, and hydrogen are the four elements that make up urea. It contains two electrons and a molar mass of 60.06 g/mole.
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Sketch the titration curve for the titration of 0.15 m formic acid with 0.25 m naoh. you can start with any initial volume of the acid, as the volumes of base added will be proportional. the shape of the titration curve will not change significantly. all acid-base titration calculations start as limiting reactant problems, followed by an equilibrium or buffer calculation. you must calculate the ph at four regions of the titration curve to label your sketch: 1. the initial ph before any naoh has been added 2. the ph at some fraction of the equivalence point 3. the ph at the equivalence point 4. the ph at some volume past the equivalence point this will be covered in lab lecture and you will also find the examples in your textbook very helpful.
1. The initial pH of the solution is 1.89.
2. At half the equivalence point (20 mL of NaOH added), the pH of the solution is 3.26.
3. At the equivalence point (30 mL of NaOH added), the pH of the solution is 10.72.
4. At some volume past the equivalence point the pH of the solution is 12.30
In the sketch (in figure), the x-axis represents the volume of NaOH added and the y-axis represents the pH of the solution. The initial pH before any NaOH has been added is 1.89, which is the pH of the 0.15 M formic acid solution.
As NaOH is added, the pH increases slowly at first, but then increases more rapidly as the solution enters the buffer region. At the half-equivalence point (20 mL of NaOH added), the pH is 3.26. At the equivalence point (30 mL of NaOH added), the pH jumps up to 10.72 due to the complete reaction of the formic acid with NaOH.
After the equivalence point, the pH continues to increase as more NaOH is added. At 50 mL past the equivalence point, the pH is 12.30, which is close to the pH of a strong base.
The titration of 0.15 M formic acid (HCOOH) with 0.25 M NaOH can be represented by the following equation:
[tex]HCOOH + NaOH[/tex] → [tex]NaCOOH + H_2O[/tex]
Before any NaOH is added, the solution consists of 0.15 M formic acid, which is a weak acid. The initial pH of the solution can be calculated using the dissociation constant (Ka) of formic acid:
[tex]HCOOH + H_2O < = > H_3O^+ + HCOO^-[/tex]
[tex]Ka = [H_3O^{+}][HCOO^{-}]/[HCOOH][/tex]
Since formic acid is a weak acid, we can assume that [tex][H_3O^+][/tex] is equal to [tex][HCOO^-][/tex]. Let x be the concentration of [tex][H_3O^+][/tex] and [[tex][HCOO^-][/tex]] at equilibrium, then:
[tex]Ka = x^2 / (0.15 - x)[/tex]
At equilibrium, the concentration of HCOOH will be (0.15 - x) M.
Let's solve for x:
[tex]Ka = x^2 / (0.15 - x)[/tex]
[tex]1.77 * 10^{-4} = x^2 / (0.15 - x)[/tex]
x = 0.0129 M
1. Therefore, the initial pH of the solution is:
[tex]pH = -log[H_3O^+][/tex]
pH = -log(0.0129)
pH = 1.89
Now let's consider the pH at different points during the titration:
Before any NaOH has been added:
The initial pH of the solution is 1.89.
2. At some fraction of the equivalence point:
At the equivalence point, all of the formic acid will have reacted with an equal amount of NaOH. Since NaOH is a strong base, the solution will be basic after the equivalence point.
At some fraction of the equivalence point, we can assume that the solution is a buffer consisting of formic acid and its conjugate base, sodium formate (NaCOOH). We can use the Henderson-Hasselbalch equation to calculate the pH:
pH = pKa + log([NaCOOH] / [HCOOH])
At the fraction of the equivalence point, we can assume that the concentration of HCOOH and NaCOOH are equal, and the concentration of NaOH is equal to the fraction of the equivalence point times the initial concentration of formic acid. Thus:
[HCOOH] = 0.15 M - (fraction of equivalence point) × (volume of NaOH added)
[NaCOOH] = (fraction of equivalence point) × (volume of NaOH added)
[tex][H_3O^+] = Ka * [HCOOH] / [NaCOOH][/tex]
Let's assume that the fraction of the equivalence point is 0.5, which means that half of the initial concentration of formic acid has reacted with NaOH. Let's also assume that we have added 20 mL of NaOH so far:
[tex][HCOOH] = 0.15 M - 0.5 * 0.02 L * 0.25 M\\[HCOOH] = 0.14 M\\[NaCOOH] = 0.5 * 0.02 L * 0.25 M\\[NaCOOH] = 0.0025 M[/tex]
[tex][H_3O^+] = 1.77 * 10^{-4} * (0.14 / 0.0025)[/tex]
[tex][H_3O^+] = 9.88 * 10^{-3} M[/tex]
[tex]pH = pKa + log([NaCOOH] / [HCOOH])\\\\pH = 3.75 + log([0.0025 / 0.14])\\\\pH = 3.26[/tex]
Therefore, at half the equivalence point (20 mL of NaOH added), the pH of the solution is 3.26.
3. At the equivalence point:
The pH can be calculated using the hydrolysis constant (Kb) of sodium formate:
[tex]NaCOOH +[/tex] [tex]H_2O[/tex] ⇌ [tex]NaOH + HCOOH[/tex]
[tex]Kb = [NaOH][HCOOH]/[NaCOOH][/tex]
Let's assume that we have added 30 mL of NaOH, which is the equivalent amount to the initial concentration of formic acid:
[tex][NaOH] = [HCOOH] = 0.15 M\\[NaCOOH] = 0.5 * 0.03 L * 0.25 M\\[NaCOOH] = 0.00375 M\\\\Kb = [NaOH]^2 / [NaCOOH]\\\\Kb = (0.15)^2 / 0.00375\\\\Kb = 6\\\\pOH = -log[OH-]\\pOH = -log\sqrt{(Kb * [NaCOOH])} \\pOH = -log\sqrt{6 * 0.00375} \\pOH = 3.28\\pH = 14 - pOH\\pH = 10.72[/tex]
Therefore, at the equivalence point (30 mL of NaOH added), the pH of the solution is 10.72.
4. At some volume past the equivalence point:
After the equivalence point, the solution will be basic due to the excess of NaOH. The pH can be calculated using the concentration of NaOH and the volume of NaOH added:
pOH = -log[OH-]
pOH = -log(0.25 × (volume of NaOH added - volume of NaOH at equivalence point))
pH = 14 - pOH
Let's assume that we have added 50 mL of NaOH past the equivalence point:
pOH = -log(0.25 × (0.05 L - 0.03 L))
pOH = 1.70
pH = 14 - pOH
pH = 12.30
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Microscope Parts and Use Worksheet
Rack Stop
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high
Microscope Part
power obiective into place
The Rack Stop is a small, movable metal stopper located at the bottom of the microscope body tube. Its purpose is to prevent the objective lenses from hitting the microscope slide or specimen, which could damage both the lenses and the sample.
Here is a list of microscope parts and their uses, including the Rack Stop:
1. Eyepiece or Ocular Lens: The lens at the top of the microscope that you look through to view the specimen.
2. Body Tube: The long, cylindrical part of the microscope that holds the eyepiece at the top and the objective lenses at the bottom
3. Arm: The curved part of the microscope that connects the body tube to the base.
4. Base: The flat, sturdy part of the microscope that supports the rest of the instrument.
5. Stage: The flat platform on which you place the specimen for viewing.
6. Stage Clips: Small metal clips that hold the microscope slide in place on the stage.
7. Coarse Focus Knob: A large knob that moves the body tube up and down to bring the specimen into rough focus.
8. Fine Focus Knob: A smaller knob that moves the body tube slightly to fine-tune the focus of the specimen.
9. Diaphragm: A rotating disc or lever that controls the amount of light entering the microscope and illuminating the specimen.
10. Light Source: The bulb or mirror that provides light for illuminating the specimen.
11. Objective Lenses: A set of lenses located at the bottom of the body tube that magnify the specimen.
12. Rack Stop: A small, movable metal stopper located at the bottom of the microscope body tube. Its purpose is to prevent the objective lenses from hitting the microscope slide or specimen.
13. Nosepiece: The rotating turret at the bottom of the body tube that holds the objective lenses.
14. High Power Objective: The objective lens with the highest magnification, typically 40x or higher. It is used for detailed examination of the specimen.
To use the microscope, first place the specimen on the stage and secure it with the stage clips. Turn on the light source and adjust the diaphragm to control the amount of light entering the microscope. Then, use the coarse focus knob to bring the specimen into rough focus. Once you have achieved this, use the fine focus knob to fine-tune the focus and bring the specimen into clear view. To change the magnification, rotate the nosepiece to select the desired objective lens. Finally, adjust the focus as needed and observe the specimen at the desired magnification.
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which of the following statements describe a reaction that is at equilibrium? a. all of the products are consumed. b. all of the reactants are consumed. c. there are no changes taking place within the reaction. d. the forward and reverse reactions are proceeding at the same rate.
In an equilibrium reaction, the forward and reverse reactions are proceeding at the same rate. option (d) is correct.
A Chemical equilibrium in a system is defined as a system in which the concentration of reactant and the concentration of products do not change with time, also the system does not display kind of change in its properties.
When the rate of forward and backward reaction is same, the system is said to have reached a dynamic equilibrium. Here, the concentrations of reactants and products become equal.
There are two types of equilibrium: homogenous equilibrium, heterogeneous equilibrium.
In homogeneous equilibrium the reactants and products are in the same phase. Whereas, in heterogeneous equilibrium the reactants and products are in different phases.
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the volume of a sample of hydrogen gas was decreased from 12.13 l 12.13 l to 5.42 l 5.42 l at constant temperature. if the final pressure exerted by the hydrogen gas sample was 7.85 atm, 7.85 atm, what pressure did the hydrogen gas exert before its volume was decreased?
Using Boyle's law, we can calculate the pressure of the hydrogen gas before its volume was decreased. According to Boyle's law: PV = k where P is pressure, V is volume, and k is a constant at constant temperature. so the answer is 3.51 atm.
We can use the equation P1V1 = P2V2 to solve for the initial pressure, where P1 is the initial pressure, V1 is the initial volume, P2 is the final pressure, and V2 is the final volume.
Substituting the given values, we get:
P1V1 = P2V2 P1(12.13 L) = (7.85 atm)(5.42 L) P1 = (7.85 atm)(5.42 L) / (12.13 L) P1 = 3.5075 atm = 3.51 atm.
Therefore, the answer is: the hydrogen gas exerted a pressure of 3.51 atm before its volume was decreased.
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A reaction at -19.0 degrees Celsius evolves 785. mmol of sulfur tetrafluoride gas. Calculate the volume of sulfur tetrafluoride gas that is collected. You can assume the pressure in the room is exactly 1 ATM. Be sure your answer has the correct number of significant digits.
The volume 16.76 L of sulphur tetrafluoride gas were collected.
The ideal gas law is used to calculate the volume of sulfur tetrafluoride collected. The ideal gas law states that PV = nRT, n is the number of gas molecules, P is the pressure in atmospheres, V is the volume of the gas in litres, R is the universal gas constant, and T is the temperature in Kelvin.
Using the information given in the problem, we can calculate the volume of sulfur tetrafluoride gas that is collected. First, convert the temperature from Celsius to Kelvin by adding 273.15. This means that the temperature in Kelvin is 254.15. Next, we can solve for V, the volume of gas collected, by rearranging the ideal gas law equation:[tex]V = \frac{nRT}{P}[/tex].
[tex]n=785.mmol,\\R=0.0821L.atm/K.mol\\T=254.14K\\\\P=1atm[/tex]
Substituting in the values, we get:
[tex]V =\frac{ (785. mmol)(0.0821 L.atm/K.mol)(254.15 K)}{(1 atm) }\\\\V= 16.76 L[/tex]
Therefore, the volume of sulfur tetrafluoride gas collected is 16.76 L.
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PLEASE HELPPPP (BOTANY ZOOLOGY)
Radial symmetry is a type of body symmetry where each plane that passes through the centre splits the body into two equally sized halves.
What exactly does bilateral symmetry mean?The capacity of an animal's body plan to be divided along a line that divides the animal's body into nearly identical right and left halves is known as bilateral symmetry. Arrangement of identical pieces in a circle around a central axis is a type of symmetry.
What does radial versus biradial symmetry mean?The organism can be divided into additional planes with identical parts in radial symmetry. In biradial symmetry, the organism can be divided solely in two planes rather than all three as in radial symmetry.
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in part a, even though the concentrations of the reactants are changed in each trial, the experimentally determined values of the rate constant, k , for each trial should be fairly similar. why is this?
As long as the temperature and other conditions are kept constant, the rate constant will remain constant for that reaction.
Part A: Why should experimentally determined values of the rate constant, k, for each trial be fairly similar, even though the concentrations of the reactants are changed in each trial,
The experimentally determined values of the rate constant k for each trial should be fairly similar even though the concentrations of the reactants are changed in each trial because the rate constant is a measure of the intrinsic reactivity of the reaction itself, and is independent of the initial concentrations of the reactants.
As long as the temperature and other conditions are kept constant, the rate constant will remain constant for that reaction.
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Express your answer as a balanced chemical equation.
The balanced reaction equation is;
2 HBr (aq) + Ca(OH)2 (s) → CaBr2 (aq) + 2 H2O (l)
What is the balanced reaction equation?A balanced chemical equation is an equation in which the number of atoms of each element is the same on both the reactant and product sides of the equation. This means that the law of conservation of mass is obeyed - the total mass of the reactants equals the total mass of the products.
The reactants and the products can be seen on the left and on the right hand sides of the reaction equations respectively.
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When the internal energy of a system decreases by 300J while 100J of work is done on the system, what is the change in the heat for the system.
A.-200
B.+400
C.-400
D.+200
The answer is (A) -200 J.
The first law of thermodynamics states that the change in the internal energy of a system, ΔU, is equal to the heat added to the system, Q, minus the work done by the system, W:
ΔU = Q - W
In this case, we know that ΔU = -300 J (decrease in internal energy) and W = 100 J (work done on the system). Therefore, we can rearrange the equation to solve for Q:
Q = ΔU + W = -300 J + 100 J = -200 J
This means that the system lost 200 J of heat. However, the question asks for the change in heat, which means we need to take the negative sign into an account. Therefore, the answer is (A) -200 J.
The first law of thermodynamics is a fundamental principle of physics that states that energy can only be moved or changed from one form to another. This theory holds true for all types of energy, including mechanical, thermal, and electromagnetic energy.
The first law of thermodynamics is concerned with the conservation of energy in a system. It says that the total energy of a closed system remains constant, which includes both the system's internal energy and the work done on or by the system.
In other words, any change in a system's energy must be balanced by a change in the work or heat entering or exiting the system.
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Ana made a poster about the different kinds of volcanoes.
Under each picture, she listed the characteristics of each kind of volcano. Read each description and drag it to the correct kind of volcano.
The description of each volcano is
loose and ashy: cinder cone volcanoalso called stratovolcano: composite volcanobuilds up over a broad area: shield volcanoerodes quickly: cinder cone volcanoslow, steady eruptions: shield volcanoalternating layers of hard lava and ash: composite volcanoWhat damages volcanoes?
Volcanoes erupt with a highly destructive mixture of ash, lava, hot, dangerous gases, and rock. Explosions from volcanoes have claimed lives.
Volcanic eruptions can bring about additional health risks like wildfires, floods, mudslides, power disruptions, and contaminated drinking water.
What places do volcanoes exist?The tectonic plate borders are home to 60% of all active volcanoes. The majority of volcanoes are situated along the Pacific Ocean's "Ring of Fire," which is a band of volcanic activity.
Some volcanoes, such as those that make up the Hawaiian Islands, develop at locations known as "hot spots" inside of plates.
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write the chemical equation for the autoionization of water. use subscripts and superscripts in the chemical formulas.
The chemical equation for the autoionization of water can be written as,
2H₂O ⇌ H₃O⁺ + OH⁻
In pure water, a small percentage of water molecules can react with each other through a process known as autoionization or self-ionization. In this equation, two water molecules (H₂O) undergo a reversible reaction to form a hydronium ion (H₃O⁺) and a hydroxide ion (OH⁻).
This process is also known as self-ionization or autoprotolysis of water. The square brackets [] are often used to indicate concentration, so the equilibrium constant for this reaction can be written as:
Kw = [H₃O⁺][OH⁻] = 1.0 x 10⁻¹⁴ (at 25°C)
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46. Sulfuric acid (H₂SO4) reacts with aqueous sodium cyanide, forming hydrogen cyanide gas and aqueous sodium sulfate.
Answer:
The balanced chemical equation for the reaction between sulfuric acid (H₂SO4) and aqueous sodium cyanide is:
H₂SO4 + 2 NaCN → 2 HCN + Na₂SO₄
In this reaction, sulfuric acid (H₂SO4) reacts with aqueous sodium cyanide (NaCN) to produce hydrogen cyanide gas (HCN) and aqueous sodium sulfate (Na₂SO₄).
To balance the equation, two moles of sodium cyanide are required for every mole of sulfuric acid. The reaction produces two moles of hydrogen cyanide and one mole of sodium sulfate for every two moles of sodium cyanide and one mole of sulfuric acid.
It's important to note that hydrogen cyanide gas is highly toxic and dangerous, and proper safety precautions must be taken when handling this chemical.
Explanation:
identify the false statement about mixtures. please choose the correct answer from the following choices, and then select the submit answer button. answer choices a compound is not considered to be a mixture. a mixture must contain 2 or more pure substances. a mixture can contain compounds and/or elements. a mixture can be separated into its constituent components only by chemical means.
The last statement is the false statement which says that A mixture can be separated into its constituent components only by chemical means.
A mixture can be separated into its constituents by both physical as well as chemical means. While homogeneous mixtures are usually separated by both chemical and physical means, heterogeneous mixtures whose components can be seen by the bare eye are usually separated by physical means.
Physical means like hand picking, distillation, filtration, and fractional distillation are widely used in the separation of mixtures. For example, a mixture of soil and water is usually separated from each other using the filtration method in which a filter paper or muslin cloth is used to filter out clear water from the mixture. Thus it is false to say that the mixtures can be separated only by chemical methods.
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The false statement about mixtures is:
"A mixture can be separated into its constituent components only by chemical means."
The correct statement is that a mixture can be separated into its constituent components by physical means such as filtration, distillation, chromatography, and so on. Chemical means are used to separate compounds into their constituent elements.
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Help what's the answer?
According to the equation, one molecule of H₂ reacts for every two molecules of C₂H₄ that respond at the particle level. One molecule of C₂H₆ is created when these molecules join.
According to the equation, 1 mole of H₂ reacts for every 1 mole of C₂H₄ that does. To create 1 mole of C₂H₆, these reactants must be combined in a ratio of 1:1.
The balanced equation for the chemical reaction is:
[tex]C_2H_4_(g_) + H_2_(g_) -- > C_2H_6_(g_)[/tex]
This equation illustrates how ethene (C₂H₄) and hydrogen gas (H₂) combine to create ethane. (C₂H₆). The stoichiometric coefficients in the equation denote the mole ratios of the reactants and products in the balanced equation. They are represented by the coefficients in the equation.
According to the equation, one molecule of H₂ reacts for every two molecules of C₂H₄ that respond at the particle level. One molecule of C₂H₆ is created when these molecules join.
According to the equation, 1 mole of H₂ reacts for every 1 mole of C₂H₄ that does. To create 1 mole of C₂H₆, these reactants must be combined in a ratio of 1:1.
In general, the balanced equation and its coefficients offer crucial details about the proportions of reactants and products engaged in the chemical reaction.
Chemical processes are modeled by chemical equations. The proportions of the reactants and products engaged in a chemical reaction are displayed in a balanced chemical equation.
The reactant's and products' mole ratios, which show the relative amounts of each substance engaged in the reaction, are represented by the coefficients in the balanced equation.
The mass conservation principle, says that mass is neither produced nor destroyed in a chemical reaction and experimental data are used to determine these coefficients.
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heparin sodium 10u/ml will be used for flushing the artery intraoperatively the vial reads heparin 10,000 u/ml. how much heparin will be added to 500ml
0.5 ml of heparin solution should be added to 500 ml to prepare heparin sodium 10 U/ml solution for flushing the artery intraoperatively.
Heparin sodium solution is a sterile, clear, colorless solution that contains heparin, a medication that is used as an anticoagulant or blood thinner. Heparin sodium solution is used to prevent blood clots from forming in conditions such as deep vein thrombosis, pulmonary embolism, and during certain medical procedures such as dialysis and heart surgery.
The solution is usually administered by injection or intravenous infusion, and is available in different strengths and volumes depending on the patient's condition and the intended use. Heparin sodium solution is stored in a cool and dry place, and should be handled and disposed of properly to avoid contamination and injury.
To prepare heparin sodium solution with a concentration of 10 U/ml using a vial of heparin 10,000 U/ml
Determine the total amount of heparin needed:
10 U/ml x 500 ml = 5,000 U
Calculate the volume of heparin solution needed:
5,000 U ÷ 10,000 U/ml = 0.5 ml
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this is a reddish-brown irritating gas that gives photochemical smog its brownish color; in the atmosphere it can also be converted in the atmosphere into an acid that is one of the major component of acid deposition, what is this substance? (give name not chemical formula)
The substance is nitrogen dioxide (NO₂).
Nitrogen dioxide (NO₂) is a reddish-brown irritating gas that is a major contributor to photochemical smog. In the presence of sunlight, it reacts with other pollutants such as volatile organic compounds (VOCs) to form ground-level ozone, which is a major component of smog. NO₂ is also a precursor to nitric acid, which is one of the major components of acid deposition.
NO₂ is mainly emitted by vehicles, power plants, and industrial processes. Exposure to high levels of NO2 can cause respiratory problems such as coughing, wheezing, and shortness of breath. It is therefore important to control NO₂ emissions to protect human health and the environment.
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Explain why C6H6 is a Lewis base, but not a Bronsted Lowry or Arrhenius base.
Answer:
C6H6, also known as benzene, is a Lewis base because it can donate a pair of electrons to form a coordinate covalent bond with a Lewis acid. A Lewis base is defined as any substance that can donate a pair of electrons to form a coordinate covalent bond.
However, benzene is not a Bronsted-Lowry base because it does not have a hydrogen ion (H+) to donate. A Bronsted-Lowry base is defined as any substance that can donate a hydrogen ion (H+).
Benzene is also not an Arrhenius base because it does not produce hydroxide ions (OH-) when dissolved in water. An Arrhenius base is defined as any substance that produces hydroxide ions (OH-) when dissolved in water.
Explanation:
There are different definitions of what a base is. Three common definitions are the Lewis, Bronsted-Lowry, and Arrhenius definitions.
According to the Lewis definition, a base is any substance that can donate a pair of electrons to form a bond. Benzene (C6H6) can do this, so it is considered a Lewis base.
The Bronsted-Lowry definition says that a base is any substance that can donate a hydrogen ion (H+). Benzene does not have a hydrogen ion to donate, so it is not considered a Bronsted-Lowry base.
The Arrhenius definition says that a base is any substance that produces hydroxide ions (OH-) when dissolved in water. Benzene does not produce hydroxide ions when dissolved in water, so it is not considered an Arrhenius base.
if you have 10ml of an 18 M solution how many ml would you need to make a 2 M solution?
To make a 2 M solution from an 18 M solution, you will need to dilute it by a factor of 9. (C1V1 = C2V2) denotes the relationship between the initial concentration (C1), initial volume (V1), final concentration (C2), and final volume (V2)
What is the concentrated solution and a diluted solution?A concentrated solution has a high solute to solvent ratio, meaning there is a large amount of solute (such as salt or sugar) dissolved in a small amount of solvent (such as water). A diluted solution has a low solute to solvent ratio, meaning there is a small amount of solute dissolved in a large amount of solvent.
What is the importance of knowing how to dilute a solution?Knowing how to dilute a solution is important in many scientific and medical applications, as it allows us to create solutions with specific concentrations that are needed for experiments or treatments.
Dilution can also be used to reduce the toxicity or reactivity of a substance, making it safer to handle or use.
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Help what's the answer??
The mass of the excess reagent (iron) that remains after the reaction is complete is 12.1 grams.
The maximum mass of Iron(III) oxide that can be formed is 74.8 grams.
The formula for the limiting reactant is O₂, which is oxygen gas.
Calculate the number of moles of each reactant:
Number of moles of iron = 38.2 g / 55.845 g/mol = 0.683 moles
Number of moles of oxygen = 14.9 g / 32.00 g/mol = 0.466 moles
The balanced equation shows that the stoichiometric ratio between iron and oxygen is 4:3. Therefore, the mole ratio of iron to oxygen is 4:3.
Since the mole ratio of iron to oxygen is greater than 4:3, it means that there is an excess of iron and oxygen is the limiting reactant. So we need to use the number of moles of oxygen to calculate the maximum mass of Iron(III) oxide that can be formed.
The balanced equation shows that 1 mole of iron reacts with 1 mole of oxygen to produce 1 mole of Iron(III) oxide. The molar mass of Iron(III) oxide is 159.69 g/mol.
Number of moles of Iron(III) oxide = 0.466 moles (which is equal to the number of moles of oxygen)
The maximum mass of Iron(III) oxide = Number of moles of Iron(III) oxide x molar mass of Iron(III) oxide
Maximum mass of Iron(III) oxide = 0.466 moles x 159.69 g/mol = 74.8 grams
The maximum mass of Iron(III) oxide that can be formed is 74.8 grams.
The formula for the limiting reactant is O₂, which is oxygen gas.
To calculate the mass of the excess reagent (iron) that remains after the reaction is complete, we need to first calculate the mass of iron that reacted with the oxygen:
Mass of iron reacted = 0.466 moles x 55.845 g/mol = 26.1 grams
The initial mass of iron was 38.2 grams, so the mass of excess iron that remains after the reaction is complete is:
Mass of excess iron = initial mass of iron - a mass of iron reacted
Mass of excess iron = 38.2 g - 26.1 g = 12.1 grams
The mass of the excess reagent (iron) that remains after the reaction is complete is 12.1 grams.
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if the concentration of 1-iodopropane quadruples and the concentration of sodium hydroxide triples in this sn2 reaction, how much faster is the reaction rate?
The reaction rate is 12 times faster when the concentration of 1-iodopropane quadruples and the concentration of sodium hydroxide triples.
In SN₂ reaction, the rate is dependent on both the concentration of the nucleophile as well as the concentration of the substrate. The rate law for this reaction can be calculated as;
rate = k[substrate][nucleophile]
where k is the rate constant and [substrate] and [nucleophile] are the concentrations of the substrate and nucleophile, respectively.
If the concentration of 1-iodopropane quadruples and the concentration of sodium hydroxide triples, then the new rate of the reaction can be calculated using the following equation:
new rate = k[(4[substrate])×(3[nucleophile])]
new rate = k[12[substrate][nucleophile]]
new rate = 12 times the original rate
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solid sodium carbonate is slowly added to 75.0 ml of a zinc bromide solution until the concentration of carbonate ion is 0.0636 m. the maximum amount of zinc ion remaining in solution is
A zinc bromide solution containing 75.0 ccs of solid sodium carbonate is gradually added until the carbonate ion concentration reaches 0.0636 m. The maximum amount of zinc ions that can remain in the solution is 5.30 x 10^-14 moles.
The addition of solid sodium carbonate to the zinc bromide solution will result in the precipitation of zinc carbonate according to the following balanced chemical equation:
Na2CO3 + ZnBr2 -> ZnCO3 + 2NaBr
The stoichiometry of the reaction shows that one mole of zinc bromide reacts with one mole of sodium carbonate to produce one mole of zinc carbonate. Therefore, the number of moles of zinc carbonate produced will be equal to the number of moles of carbonate ion in the solution, which is given as 0.0636 moles.
The initial concentration of zinc bromide is not given, so we cannot directly calculate the number of zinc ions remaining in the solution. However, we can use the solubility product constant (Ksp) of zinc carbonate to determine the maximum amount of zinc ions that can remain in the solution before precipitation occurs.
The Ksp of zinc carbonate is given as 4.5 x 10^-11. Using the balanced chemical equation, we can write the expression for the Ksp as follows:
Ksp = [Zn2+][CO32-]
Since the concentration of carbonate ion is given as 0.0636 M, we can rearrange the above equation to solve for the maximum concentration of zinc ion that can remain in the solution:
[Zn2+] = Ksp / [CO32-] = (4.5 x 10^-11) / (0.0636)
= 7.07 x 10^-13 M
Therefore, the maximum amount of zinc ion that can remain in the solution is given by multiplying the maximum concentration by the final volume of the solution:
[Zn2+] x Vfinal = (7.07 x 10^-13 M) x (75.0 mL / 1000 mL/mL)
= 5.30 x 10^-14 moles
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In digestion system ,evidence of a chemical change can be observed when
Answer:
Explanation:
What is chemical digestion?
When it comes to digestion, chewing is only half the battle. As food travels from your mouth into your digestive system, it’s broken down by digestive enzymes that turn it into smaller nutrients that your body can easily absorb.
This breakdown is known as chemical digestion. Without it, your body wouldn’t be able to absorb nutrients from the foods you eat.
How is chemical digestion different from mechanical digestion?
Chemical and mechanical digestion are the two methods your body uses to break down foods. Mechanical digestion involves physical movement to make foods smaller. Chemical digestion uses enzymes to break down food.
Mechanical digestion
Mechanical digestion begins in your mouth with chewing, then moves to churn in the stomach and segmentation in the small intestine. Peristalsis is also part of mechanical digestion. This refers to involuntary contractions and relaxations of the muscles of your esophagus, stomach, and intestines to break down food and move it through your digestive system.
Chemical digestion
Chemical digestion involves the secretions of enzymes throughout your digestive tract. These enzymes break the chemical bonds that hold food particles together. This allows food to be broken down into small, digestible parts.
what weight of potassium hydrogen phthalate will require 40.0 ml of a 0.100 m naoh solution to reach the equivalence point?
The weight of potassium hydrogen phthalate that will require 40.0 ml of a 0.100 m NaOH solution to reach the equivalence point is 0.8169 grams.
In order to find out the weight of potassium hydrogen phthalate that will require 40.0 ml of a 0.100 m NaOH solution to reach the equivalence point, we can use the following formula: weight of KHP = (molarity of NaOH) x (volume of NaOH) x (molar mass of KHP) / 1000
First, we need to calculate the number of moles of NaOH required to reach the equivalence point: Moles of NaOH = (molarity of NaOH) x (volume of NaOH) / 1000 Moles of NaOH = (0.100 mol/L) x (40.0 mL) / 1000 Moles of NaOH = 0.004 mol.
Now we can use the number of moles of NaOH to calculate the weight of KHP required: Weight of KHP = (0.004 mol) x (204.22 g/mol), Weight of KHP = 0.8169 g. Therefore, the weight of potassium hydrogen phthalate that will require 40.0 ml of a 0.100 m NaOH solution to reach the equivalence point is 0.8169 grams.
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Which of the following materials will allow sound to travel the fastest?
A) water
B) lead
C) air
D) glass
Answer:
solid this is because molecules in a sound medium are much closer together than those in a liquid or gas
(e) The table shows some information about an investigation on the decomposition of H2O2(aq) using two different catalysts. In each experiment, 0.100g of the catalyst and
25.0 cm3 of H2O2(aq) were used. The concentration and temperature of the H2O2(aq) Use were kept constant.
manganese(IV) oxide 25 95
peroxidase 10
For Examiner’s
catalyst
time taken to collect 50 cm3 of oxygen / s
total volume of oxygen made at the end of the reaction / cm3
© UCLES 2010
5070/21/M/J/10
(i)
(ii)
What is the total volume of oxygen made at the end of the reaction in which peroxidase was used as a catalyst?
volume of oxygen = ............................. cm3
The volume of oxygen made at the end of the reaction in which peroxidase was used as a catalyst is 10 cm3.
Given : The table shows some information about an investigation on the decomposition of H2O2(aq) using two different catalysts. In each experiment, 0.100g of the catalyst and 25.0 cm3 of H2O2(aq) were used. The concentration and temperature of the H2O2(aq) Use were kept constant.
Manganese(IV) oxide 25 95 Peroxidase 10.
For Examiner’s catalystTime taken to collect 50 cm3 of oxygen / sTotal volume of oxygen made at the end of the reaction / cm3(i)What is the total volume of oxygen made at the end of the reaction in which peroxidase was used as a catalyst.
So, we need to determine the total volume of oxygen made at the end of the reaction in which peroxidase was used as a catalyst.Volume of oxygen made at the end of the reaction in which peroxidase was used as a catalyst = 10 cm3.
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