The pH of the resulting solution after the addition of 13.0 mL of 0.100 M HCl is 4.7. This indicates that the solution is acidic and that there is still some of the weak acid HA remaining in the solution.
The addition of the strong acid HCl will react with the weak base A- produced during the titration, forming the weak acid HA and neutralizing some of the OH- ions present. This will result in a lower pH than the pH at the equivalence point, and the difference between the two pH values can be used to calculate the dissociation constant (pKa) of the weak acid.
At the equivalence point, the pH is determined by the dissociation constant (Ka) of the weak acid. In this case, the pale-pink phenolphthalein endpoint indicates that the pH at the equivalence point is approximately 8.5-9.5.
Since the pH at the equivalence point is higher than the pH of 4.7 after the addition of HCl, the weak acid must be less dissociated at the latter pH.
This means that the pKa of the weak acid is higher than the pH of 4.7, because a higher pKa corresponds to a weaker acid and a lower degree of dissociation.
Therefore, we can conclude that the pKa of the unknown weak acid HA is greater than 4.7, based on the pH of the resulting solution after the addition of HCl.
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when the student read the eudiometer tube to record the volume of h2 gas, he read the edge of the meniscus instead of the center. how will this affect the measured volume of the gas?
Reading the edge of the meniscus instead of the center of the meniscus will result in an inaccurate measurement of the volume of the gas.
The meniscus should be read at the middle of the curve, not the edge, when using the eudiometer tube.
The volume of the gas will be more than the real volume if the meniscus' edge is read rather than the centre since the edge is higher than the centre.
The eye should be level with the meniscus's centre when reading the tube for the most precise measurement. Inaccurate calculations and faulty findings can occur from measuring the gas's volume incorrectly.
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16.2296 rounded in significant figure
16.2296 has 6 significant figures and 4 decimals. 16.2296 rounded to 5 sig figs is 16.230, to 4 sig figs is 16.23, and to 3 sig figs is 16.2. To count the number of sig figs in 16.2296, count all 6 digits since it has no insignificant digits (all digits are significant).
Result 16.2296
Result 16.2296Sig Figs 6 (16.2296)
Result 16.2296Sig Figs 6 (16.2296)Decimals 4 (16.2296)
Result 16.2296Sig Figs 6 (16.2296)Decimals 4 (16.2296)Scientific Notation 1.62296 × 101
E-Notation. 1 .62296e+1
.62296e+1Words sixteen point two two nine six
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consider the following oxides: so2 , p2o5 , mgo , cl2o , n2o5 . how many are expected to form acidic solutions in water?
Metal oxides form basic solutions while nonmetal oxides form acid solutions. SO₂, P₂O₅, Cl₂O, and N₂O₅ oxides are predicted to generate acidic solutions.
The periodic table's left side is where metals are located. Oxides are created when metals and oxygen react. Metal oxides disintegrate in water to create basic solutions. The oxides that should result in the formation of a basic solution are MgO,
Oxygen and nonmetals can also react to generate oxides. Nonmetal oxides dissolve in water to produce acids. Hence, SO₂, P₂O₅, Cl₂O, and N₂O₅ oxides are predicted to generate acidic solutions.
Metal oxides have a basic character, whereas non-metal oxides have an acidic nature. Metal oxides are basic because when they dissolve in water, they produce salt and water. Metal oxides include OH⁻. Ions are thus fundamental. H⁺ ions are found in non-metal oxides like sulphur dioxide, which dissolve in water to create acidic solutions.
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2. calculate the temperature in oc when 2.50 moles of argon occupy 25.0 l at 1.20 atm. write the ideal gas equation and give the units for each term.
The temperature when 2.50 moles of argon occupy 25.0 l at 1.20 atm. calculated is -126. 9°C. The Ideal gas equation is,
PV = n RT
Number of moles = 2.50 moles
V= 25.0 L
P= 1.20 atm.
Ideal gas equation can be written as,
PV = n RT
The Ideal gas equation is defined as the equation which equates the product of the pressure and the volume of one mole of a gas to the product of its thermodynamic temperature and the gas constant. It is also called as the general gas equation which designates the equation of state of a hypothetical ideal gas. This equation is a good approximation of the behavior of many gases under many conditions instead of it has several limitations.
putting all the values we get,
T = -126. 9°C
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a mineral deposit along a strip of length 1 cm has density g/cm for . calculate the total mass of the deposit. your answer must include units.
The total mass of the deposit along a strip of length 1 cm that has density g/cm is simply g.
In order to calculate the total mass of a mineral deposit along a strip of length 1 cm that has density g/cm, we can use the formula: mass = density x volume The volume of the deposit is equal to the product of its length, width, and height. Since the deposit is along a strip of length 1 cm, we can assume that its width and height are negligible. Therefore, the volume of the deposit is approximately 1 cm³.
Substituting the density of the deposit in place of g/cm³, we can rewrite the formula as: mass = (density in g/cm³) x (volume in cm³)mass = g x 1 cm³mass = g To express the mass of the deposit in units of grams (g), we must know the value of the density in g/cm³. Once we know this value, we can multiply it by 1 cm³ to obtain the mass in grams.
For example, if the density of the deposit is 2 g/cm³, then the mass of the deposit is: mass = 2 g/cm³ x 1 cm³mass = 2 g Therefore, the total mass of the mineral deposit along a strip of length 1 cm that has density g/cm is simply g.
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Consider the titration of 100.0 mL of 0.100 M H2NNH2 by 0.200 M HNO3. Calculate the pH of the resulting solution after the following volumes of HNO3 have been added.
a. 0.0 mL
pH =
b. 20.0 mL
pH =
c. 25.0 mL
pH =
d. 40.0 mL
pH =
e. 50.0 mL
pH =
f. 100.0 mL
pH =
the titration of 100.0 mL of 0.100 M H₂NNH₂ by 0.200 M HNO₃
a. pH = 11.94
b. pH = 7.51
c. pH = 7.08
d. pH = 4.57
e. pH = 4.00
f. pH = 1.50
Through the addition of a known quantity of a reactant with a known concentration to the solution until the reaction is complete, the chemical process of titration can be used to determine the concentration of a specific component in a solution. The equivalency point designates the point at which the reaction has ended. When the amount of the substance being studied in the solution is equal to the amount of the added reactant, this is accomplished. To measure the quantity of acids, bases, and other compounds in a sample, analytical chemistry frequently uses titration. An indicator is used in the procedure, and after the reaction is finished, it changes colour, allowing the experimenter to locate the equivalence point. The meticulous measuring of for accurate titration,
A-pH = 14 - pOH = 14 - (-log[OH-]) = 11.94
B-pH = pKa + log([NO3-]/[H2NNH2]) = 8.00 + log(0.0333/0.0800) = 7.51
C-pH = pKa + log([NO3-]/[H2NNH2]) = 8.00 + log(0.0300/0.0625) = 7.08
D-pH = pKa + log([NO3-]/[H2NNH2]) = 8.00 + log(0.0357/0.0500) = 4.57
E-pH = pH of HNO3 solution = 1.18
F-pH = pH of HNO3 solution = 1.00
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1)
2)
Types of Chemical Reaction Worksheet
A. Balance the reactions 1 to 6 and indicate which type of chemical reaction
(synthesis, decomposition, single-displacement, double- displacement or
combustion) is being represented:
3)
4)
5)
6)
―
C₂H₂ +
C₂H18 +
FeCl3 +
P+
HNO3 +
-
-
O₂ →
_0₂.
NaOH →
_ą₂ →
_H₂O + O₂ → H₂O₂
▬▬
2) Pb + FeSO,
CO₂ +
_P₂0₁
3) 2 BF, + 3 H₂O
CO₂ +
5) 2 Fe + O₂ +
H₂O
NaHCO3 → NaNO3 + H₂O + CO₂
H₂O
Fe(OH)3 +
NaCl
B. Identify the type of reaction as synthesis, decomposition,
single-replacement, double-replacement, and combustion:
1) Na,PO, + 3 KOH
→3 NaOH + K,PO,
PbSO, + Fe
- B₂0, + 6 HF
4) 2 AI + 6 HCI 2 AICI, + 3 H₂
Reaction Type:
Reaction Type:
Reaction Type:
2 H₂O2 Fe(OH),
Reaction Type:
Reaction Type:
Reaction Type:
the ele
Chemical reactions can be classified into several different types based on their characteristics and the nature of the reactants and products involved.
What are the reaction types?Synthesis reaction involves two or more reactants combining to form a single product. The general form of this reaction is: A + B → AB.
The reaction types are;
1) Oxidation reaction
2) Oxidation reaction
3) Double replacement reaction
4) Synthesis reaction
5) Double replacement reaction
6) Synthesis reaction
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what is the concentration of h in a 0.025 m hcl solution? group of answer choices 0.010 m 0.013 m 0.025 m 0 0.050 m
Answer:
0.025
Explanation:
The concentration is 0.025 since that is the molarity of the solution. Molarity is mol/L . Molarity is the concentration of the HCl
Answer is 0.025
The concentration of H+ in a 0.025 M HCl solution is 0.025 M, since HCl is a strong acid and dissociates completely in water to form H+ and Cl-.
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what happens in a reduction?
Answer:
Reduction is a process where a substance: Gains one or more electrons. Loses an oxygen atom or Electronegative atoms. Gains a hydrogen atom or Electropositive atoms.
Explanation:
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Answer:
In a chemical reaction, reduction is a process in which a molecule or ion gains electrons, resulting in a decrease in oxidation state. This process typically involves the transfer of electrons from one molecule to another, resulting in the production of a reduced product.
Explanation:
During a reduction reaction, a molecule or ion (the oxidizing agent) accepts electrons from another molecule or ion (the reducing agent). The reducing agent transfers electrons to the oxidizing agent, which causes it to become reduced. At the same time, the reducing agent becomes oxidized as it loses electrons.For example, in the reaction between copper ions and zinc metal, the copper ions are reduced to copper metal while the zinc metal is oxidized to zinc ions:
Cu2+ + 2e- → Cu (reduction - gaining electrons)Zn → Zn2+ + 2e- (oxidation - losing electrons)COUNTER CLAIM:
Overall, reduction is a process in which electrons are gained, resulting in a decrease in oxidation state, and it is often paired with oxidation, which is a process of losing electrons and an increase in oxidation state. The combination of these two processes is known as a redox reaction.NEED ANSWER ASAP
Which of the following is an example of how thermal energy moves in a predictable pattern?
F.Ice in the freezer that stays frozen
G.Ice in a glass of water on the table that melts after ten minutes
H.Water in a glass on the table that freezes after 40 minutes
J.None of the above
J. None of the above.
The total amount of energy in a closed system is conserved, meaning that it cannot be created or destroyed, only transformed from one form to another.
What is Energy?
Energy is a physical quantity that measures the ability of a system to perform work. It is an abstract concept that comes in many forms, such as mechanical, thermal, electrical, chemical, and nuclear energy. Energy can be transferred between different objects or systems, and it can be converted from one form to another.
Option H is an example of how thermal energy moves in a predictable pattern. When water is left on a table at a low temperature for a long period of time, its temperature drops below the freezing point of water, and the water molecules start to form ice crystals. This is an example of a predictable pattern in which thermal energy is transferred from the water to the surrounding air, causing the water to freeze.
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ammonia chemically reacts with oxygen gas to produce nitric oxide and water . what mass of nitric oxide is produced by the reaction of of oxygen gas?
They want to know the mass of nitric oxide that is produced by this reaction. The balanced chemical equation for this reaction is:
4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)
In this equation, 4 moles of NH₃ react with 5 moles of O₂ to produce 4 moles of NO and 6 moles of H₂O. To find the mass of NO produced, we need to use the molar mass of NO. Molar mass of NO = 30.01 g/molTo find the mass of NO produced, we need to use stoichiometry.
We know that 4 moles of NH₃ reacts with 5 moles of O₂ to produce 4 moles of NO. Therefore, if we know the number of moles of O₂ that reacted, we can use stoichiometry to find the number of moles of NO produced.We can use the ideal gas law to find the number of moles of O₂ that reacted.
n = PV/RT We can assume that the reaction took place at standard temperature and pressure (STP), which means:P = 1 atmV = 22.4 L (molar volume of an ideal gas at STP)T = 273.15 K (0 °C)R = 0.08206 L atm/(mol K)Using these values, we can find the number of moles of O₂ that reacted:n = PV/RT = (1 atm)(22.4 L)/(0.08206 L atm/(mol K) * 273.15 K) ≈ 1 mol
Therefore, 1 mole of O₂ reacted in the reaction. Using stoichiometry, we can find the number of moles of NO produced.4 moles NH₃ : 4 moles NO1 mole O₂ : 4/5 moles NO (from the balanced equation)1 mole O₂ was consumed, so the number of moles of NO produced is:1 mole O₂ * (4/5 moles NO/1 mole O₂) = 0.8 moles NO
Finally, we can find the mass of NO produced using the molar mass of NO:mass NO = number of moles * molar mass mass NO = 0.8 mol * 30.01 g/mol ≈ 24.0 g Therefore, approximately 24.0 grams of NO are produced by the reaction between ammonia and oxygen gas.
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agi , baf2 , and agbr are all sparingly soluble salts. which of these salts will be more soluble in an acidic solution than in water?
sparingly soluble salts derived from weak acids tend to be more soluble in an acidic solution.
This is because the added H+ ions (from a strong acid such as HCl) react with the anions of the salts to form weak acids, which decrease the ion product and shift the equilibrium to favor more dissolution. Therefore, out of the three salts you mentioned, BaF_2 will be more soluble in an acidic solution than in water. This is because F- is the conjugate base of HF, a weak acid, while Ag+ and Br- are the conjugate acids of strong bases (AgOH and KOH).
The solubility product constant (Ksp) of BaF_2 is a measure of how much BaF_2 can dissolve in water at a given temperature. It is defined as the product of the concentrations of Ba^2+ and F^- ions in equilibrium with solid BaF_2. According to Bartleby1, the solubility product constant for BaF_2 is 1.0 x 10^-6 at 25°C. This means that only a very small amount of BaF_2 can dissolve in water at this temperature.
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of the following, the entropy of gaseous is the largest at 25ec and 1 atm. a) c2h2 b) h2 c) c2h6 d) ch4 e) c2h2
The entropy of gaseous H₂ (hydrogen gas) is the largest at 25°C and 1 atm. Option B is correct.
Entropy is a measure of the disorder or randomness of a system. In general, the entropy of a substance increases as it goes from a solid to a liquid to a gas. At the same temperature and pressure, the entropy of a substance is proportional to the number of particles in the system.
H₂ has the smallest molecular weight, which means that it has the greatest number of particles per unit volume compared to the other molecules. Therefore, it has the largest entropy at a given temperature and pressure.
Furthermore, H₂ is a diatomic gas, meaning that it has two atoms per molecule. Diatomic gases have more degrees of freedom than monoatomic gases, which also increases their entropy. C₂ H₂ (acetylene) is also a diatomic gas, but it has a larger molecular weight than H₂, so it has a lower entropy. In summary, the entropy of gaseous H₂ is the largest at 25°C and 1 atm due to its small molecular weight and diatomic nature. Option B is correct.
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A gas absorbs 5.1 kJ of heat and does 3.6 kJ of work. Calculate ΔE.
A gas absorbs 5.1 kJ of heat and does 3.6 kJ of work then the change in internal energy of the gas is 8.7 kJ.
The first law of thermodynamics states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system. Mathematically, this can be expressed as:
ΔE = Q - W
where ΔE is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.
In this problem, Q = 5.1 kJ (heat absorbed by the gas) and W = -3.6 kJ (work done by the gas, with the negative sign indicating work done on the surroundings). Plugging these values into the formula, we get:
ΔE = Q - W
ΔE = 5.1 kJ - (-3.6 kJ)
ΔE = 5.1 kJ + 3.6 kJ
ΔE = 8.7 kJ
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if you have 100 g of naoh and 100 g of al to perform the reaction, how many grams of h2 will you produce?
2.5 grams of [tex]H_{2}[/tex] will produce to perform the reaction.
[tex]2Al+2NaOH+2K_{2} O[/tex] ⇒ [tex]2Na_{3} AlO_{3} +3H_{2}[/tex]
The reactants have the following molar masses: M(NaOH) = 40 g/mol, and M(Al) = 27 g/mo.
Given,
100 g of NaOH.
100 g of Al
The reactants' total moles are:
() =()/() = 100/27 = 3.7
() = ()/() = 100/40 = 2.5 l
Then we calculate a ratio:
6 moles of NaOH and 2 moles of Al react,
3.7 moles of Al should react with x moles of NaOH, where x = 3.7* 6 /2 = 11.1 moles of NaOH.
The limiting reactant is sodium hydroxide as there are only 2.5 moles of it. To determine the mass of H2 that could be created by the chemical reaction, we must use a different percentage.
3 moles of H2 are produced from 6 moles of NaOH.
NaOH 2.5 moles - x moles H2
=2.5* 3/6 = 1.25 2
mass of [tex]H_{2}[/tex] = n([tex]H_{2}[/tex]) * M([tex]H_{2}[/tex]) = 1.25* 2 = 2.5 gm
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the solubility of calcium sulfate at a given temperature is 0.08152 g/l. calculate the ksp at this temperature.
The Ksp of calcium sulfate at the given temperature is 3.59 x 10^-7, calculated from the solubility of 0.08152 g/L using the Ksp expression.
The Ksp (solvency item steady) of calcium sulfate at the given temperature can be determined utilizing the dissolvability data gave. In the first place, the substance condition for the separation of calcium sulfate into its particles should be composed: CaSO4 ⇌ Ca2+ + SO42-. The solvency of calcium sulfate is given as 0.08152 g/L, which is identical to 0.000672 moles/L (utilizing the molar mass of calcium sulfate).
Since the stoichiometry of the separation condition is 1:1, the centralization of calcium particles and sulfate particles in the arrangement is additionally 0.000672 M. At last, the Ksp can be determined by duplicating the centralization of calcium particles and sulfate particles together: Ksp = [Ca2+][SO42-] = (0.000672 M)(0.000672 M) = 4.529 x 10^-7. Thusly, the Ksp of calcium sulfate at the given temperature is 4.529 x 10^-7.
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Pretest: Unit 2
Question 7 of 20
Which energy transfer occurs when a cube of ice is placed in a glass of
water?
O A. The chemical energy of the ice is transferred to the liquid wat
The energy transfer that occurs when a cube of ice is placed in a glass of water is a form of heat transfer known as "heat exchange" or "heat transfer by conduction".
What is heat transfer?
Heat always moves from a warmer object to a cooler one, and in this case, the ice cube is at a lower temperature than the liquid water, so heat moves from the water to the ice cube.
As the ice cube absorbs heat energy from the water, the ice melts and the temperature of the water decreases. This process continues until the ice has completely melted and the water and ice are at the same temperature.
So, to answer the question directly, the energy transfer that occurs when a cube of ice is placed in a glass of water is not a transfer of chemical energy from the ice to the water, but rather a transfer of thermal energy from the water to the ice.
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Complete question is: "heat exchange" or "heat transfer by conduction" occurs when a cube of ice is placed in a glass of water.
Consider the titration of 100.0 mL of 0.100 M H2NNH2 (Kb = 0.000003) by 0.200 M HNO3. Calculate the pH of the resulting solution after the following volumes of HNO3 have been added.
a. 0.0 mL
pH =
b. 20.0 mL
pH =
c. 25.0 mL
pH =
d. 40.0 mL
pH =
e. 50.0 mL
pH =
f. 100.0 mL
pH =
Answer:
A = 11.74
B = 9.18
C = 10.4
D = 8.10
E = 7.21
F = 1.70
For more context, you may check the explanation :)
Explanation:
This is a basic titration problem where an amine, H2NNH2, is being titrated with an acid, HNO3. The reaction between the two is:
H2NNH2 + HNO3 → H2NNH3+NO3-
The Kb value for H2NNH2 is given as 0.000003, which allows us to calculate the Kb expression:
Kb = [H2NNH3+][OH-] / [H2NNH2]
At the start of the titration, before any HNO3 is added, we have only H2NNH2 in solution and no H2NNH3+ or OH-. Therefore, at the start of the titration:
Kb = [H2NNH3+][OH-] / [H2NNH2]
0.000003 = (x)(x) / (0.100)
x = 0.0055 M
So at the start of the titration, [H2NNH2] = 0.100 M and [OH-] = 0.0055 M. To find the pH, we can use the fact that:
pH + pOH = 14
a. Before any HNO3 is added, the [OH-] is 0.0055 M. Therefore:
pOH = -log(0.0055) = 2.26
pH = 14 - 2.26 = 11.74
The pH of the solution is 11.74.
b. At 20.0 mL of HNO3 added, we can calculate the moles of HNO3 added:
moles of HNO3 = (0.200 M)(0.020 L) = 0.004 mol
This amount of HNO3 reacts completely with the same amount of H2NNH2, so the moles of H2NNH2 remaining is:
moles of H2NNH2 = 0.100 mol - 0.004 mol = 0.096 mol
The total volume of the solution is now 0.100 L + 0.020 L = 0.120 L. Therefore, the concentration of H2NNH2 is:
[H2NNH2] = 0.096 mol / 0.120 L = 0.800 M
Using the Kb expression, we can find the [OH-]:
Kb = [H2NNH3+][OH-] / [H2NNH2]
0.000003 = (x)(0.004) / (0.800)
x = 0.000015 M
Therefore, the pOH is:
pOH = -log(0.000015) = 4.82
And the pH is:
pH = 14 - 4.82 = 9.18
The pH of the solution is 9.18.
c. At 25.0 mL of HNO3 added, we can use the same approach as above to find that the concentration of H2NNH2 is 0.625 M, the [OH-] is 0.00004 M, and the pH is 10.4.
d. At 40.0 mL of HNO3 added, we can use the same approach as above to find that the concentration of H2NNH2 is 0.200 M, the [OH-] is 0.00080 M, and the pH is 8.10.
e. At 50.0 mL of HNO3 added, we can use the same approach as above to find that the concentration of H2NNH2 is 0.100 M, the [OH-] is 0.00155 M, and the pH is 7.21.
f. At 100.0 mL of HNO3 added, we can use the same approach as above to find that the concentration of H2NNH2 is 0.0 M, the [OH-] is 0.02000 M, and the pH is 1.70.
why is it common practice to rinse the solids obtained from the recrystallization with a small quantity of the cold solvent used in the procedure? (check all that apply.)
It is common practice to remove impurities from the reconstituted product by rinsing the solids obtained from the reconstituted with a small volume of cold solvent used in the process. Here option B is the correct answer.
The common practice of rinsing the solids obtained from recrystallization with a small quantity of the cold solvent used in the procedure serves to remove any residual impurities from the recrystallized product.
This is done by dissolving any residual impurities present in the crystals, which are then removed along with the solvent through filtration. The small quantity of cold solvent used is not enough to dissolve any of the pure crystals, so the recrystallized product remains pure.
Rinsing also helps to remove any residual solvent present in the crystals, which could affect the yield and purity of the product. In summary, the rinsing step is necessary to ensure that the recrystallized product is pure and free from any residual impurities or solvents that could affect its properties or intended use.
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Complete question:
Why is it common practice to rinse the solids obtained from the recrystallization with a small quantity of the cold solvent used in the procedure?
A) To increase the yield of the recrystallized product
B) To remove impurities from the recrystallized product
C) To remove residual solvent from the recrystallized product
D) To reduce the size of the crystals in the recrystallized product
E) To prevent the crystals from drying out and losing their purity
A chemical reaction occurred when .500g of Calcium hydroxide falls into a 100ml of 8.5M hydroiodic acid.Is this enough calcium hydroxide to completely neutralize the all of the acid?
-How much salt forms in this reaction?
To determine if there is enough calcium hydroxide to completely neutralize the acid, we need to calculate how much hydroiodic acid is present in 100 ml of 8.5 M solution:
moles of Hl = molarity × volume = 8.5 M × 0.1 L = 0.85 moles
How to calculate how much calcium hydroxide is present?moles of Ca(OH)2 = mass ÷ molar mass = 0.500 g ÷ 74.1 g/mol = 0.00675 moles
The balanced chemical equation for the reaction is:
Ca(OH)2 + 2 HI → CaI2 + 2 H2O
According to the balanced equation, 1 mole of Ca(OH)2 reacts with 2 moles of HI to produce 1 mole of CaI2. Therefore, the maximum amount of CaI2 that can be formed is:
0.00675 moles of Ca(OH)2 × (1 mole CaI2 ÷ 1 mole Ca(OH)2) = 0.00675 moles CaI2
However, we have 0.85 moles of HI present, which is much more than the amount needed to react with all of the Ca(OH)2. Therefore, the Ca(OH)2 is in excess, and there will be some Ca(OH)2 left over after the reaction.
The amount of Ca(OH)2 that reacts with the HI is:
0.85 moles of HI ÷ 2 = 0.425 moles of Ca(OH)2
The amount of Ca(OH)2 left over is:
0.00675 moles of Ca(OH)2 - 0.425 moles of Ca(OH)2 = -0.41825 moles of Ca(OH)2
This negative value indicates that all of the Ca(OH)2 reacts with the HI, and there is no Ca(OH)2 left over. Therefore, the Ca(OH)2 is enough to completely neutralize the acid.
The amount of CaI2 that forms is:
0.425 moles of Ca(OH)2 × (1 mole CaI2 ÷ 1 mole Ca(OH)2) × (293.9 g CaI2 ÷ 1 mole CaI2) = 124.9 g CaI2
Therefore, 124.9 g of CaI2 forms in this reaction.
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Finish the sentence. Cold air molecules heat up when they touch the warm ground through the process of ______________.
Density
Radiation
Conduction
Evaporation
Answer:
Conduction
Explanation:
Conduction is the transfer of heat energy from one substance to another or within a substance.
Cold air molecules heat up when they touch the warm ground through the process of conduction.
What is conduction ?Conduction is the transfer of heat or energy between two objects that are in contact with each other, or between different parts of the same object, due to a temperature difference.
In conduction, heat energy is transferred through a material or substance from higher-temperature regions to lower-temperature regions.
Conduction occurs because the molecules in a substance are in constant motion and collisions between them can transfer energy. When two objects are in contact, the faster-moving molecules in the warmer object collide with the slower-moving molecules in the cooler object, transferring energy from the warmer object to the cooler one.
This process continues until the two objects reach thermal equilibrium, meaning they have the same temperature.
Materials that are good conductors of heat, such as metals, allow energy to be transferred quickly through them. On the other hand, materials that are poor conductors of heat, such as plastics or insulators, prevent or slow down the transfer of energy.
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Prop-2-en-1-ol (allyl alcohol) has the following structure. Which reagent would react with prop-2-en-1-ol to form a product that could exist as optical isomers?
The reaction of prop-2-en-1-ol with HBr in the presence of a peroxide catalyst would produce a product that exists as optical isomers.
Prop-2-en-1-ol (allyl alcohol) has a chiral center, which means that it can exist as optical isomers. To form a product that could exist as optical isomers, the reagent should react with the chiral center of the molecule, causing it to become asymmetric.
One reagent that could achieve this is hydrogen bromide (HBr) in the presence of a peroxide catalyst. This reaction, known as hydrobromination, involves the addition of HBr across the double bond of prop-2-en-1-ol to form 2-bromopropan-1-ol. The addition of HBr to the double bond creates a new chiral center, which results in the formation of two enantiomers of the product.
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An unknown gas diffuses 0.25 times as fast as He, What is the molecular mass of the
unknown gas?
The molecular mass of the unknown gas = 64g/mol
The rate of diffusion of a gas is inversely proportional to the square root of its molecular mass. Let the molecular mass of the unknown gas be M. Then, we have:
Rate of diffusion of unknown gas / Rate of diffusion of He = sqrt(MHe / M)
Since the rate of diffusion of the unknown gas is 0.25 times that of He, we can write:
0.25 = sqrt(MHe / M)
Squaring both sides, we get:
0.0625 = MHe / M
M = MHe / 0.0625
The molecular mass of He is approximately 4 g/mol. Substituting this value, we get:
M = 4 / 0.0625
M = 64 g/mol
Therefore, the molecular mass of the unknown gas is approximately 64 g/mol.
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HELPPPP mg + 2 hcl ➞ mgcl2 + h2 how many grams of mgcl2 are produced by 2.55 mol mg ??
According to the correctly balanced chemical equation, 1 mole of magnesium interacts with 2 moles of HCl to create 1 mole of MgCl2 and 1 mole of hydrogen. 243.28 grams of MgCl2 will be created from 2.55 mol of Mg.
What does Mg 2hcl MgCl2 h2 produce?Single displacement reactions take place when one element is swapped out for another in a compound. Magnesium metal and hydrochloric acid combine in the reaction described to produce magnesium chloride and hydrogen gas.
According to the equation, Mg and MgCl2 have a mole ratio of 1:1, meaning that 1 mole of Mg will result in 1 mole of MgCl2.
As a result, 2.55 mol of Mg will react to form 2.55 mol of MgCl2.
We must know the molar mass of the created MgCl2 in order to determine its mass. MgCl2 has a molar mass of:
MgCl2 = 24.31 g/mol (Mg) + 2(35.45 g/mol) (Cl)
MgCl2 = 95.21 g/mol
So, the mass of MgCl2 produced from 2.55 mol of Mg is:
Mass of MgCl2 = number of moles of MgCl2 x molar mass of MgCl2
Mass of MgCl2 = 2.55 mol x 95.21 g/mol
Mass of MgCl2 = 243.28 g
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a 20.0 ml solution of naoh is neutralized with 32.5 ml of 0.200 m hbr. what is the concentration of the original naoh solution?
The concentration of the original NaOH solution is 0.325M. Molarity is sometimes referred to as substance, molarity, or concentration in terms of amount. It is a means to determine the concentration of a certain chemical species. In terms of quantity, it alludes to the material in a unit solution volume.
Balanced chemical equation:
[tex]1NaOH+1HBr[/tex] ⇒ [tex]NaBr+H_{2} O[/tex]
Given,
1). volume of HBr(V1) = 32.5ml
molarity of HBr(M1) = 0.200M
moles n1 =1
2). volume of NaOH(V2) = 20.0ml
molarity of NaOH(M2) =?
moles n2 = 1
Moles of NaOH = Moles of HBr
Molarity of HBr × Volume of HBr= Molarity of NaOH × Volume of NaOH
[tex]\frac{M1V1}{n1} = \frac{M2V2}{n2} \\[/tex]
[tex]\frac{0.2*32.5}{1} = \frac{M2*20}{1}[/tex]
M2 = 0.2*32.5/20
M2 = 6.5/20
M2 = 0.325M
Molarity of NaOH = 0.325M
the concentration of the original NaOH solution is 0.325M.
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a 50.0- ml volume of 0.15 m hbr is titrated with 0.25 m koh . calculate the ph after the addition of 17.0 ml of koh .
The pH after the addition of 17.0 mL of KOH is 0.602.
When answering questions on the platform Brainly, you should always be factually accurate, professional, and friendly. You should be concise and not provide extraneous amounts of detail. You should also use the terms in the student's question to provide an accurate answer.
Here is the solution to the given problem:Given:Volume of HBr = 50.0 mL
Concentration of HBr = 0.15M
Concentration of KOH = 0.25 M
Volume of KOH added = 17.0 mL
We need to calculate the pH after the addition of KOH.The balanced chemical equation for the reaction between HBr and KOH is:
HBr + KOH → KBr + H2O
Initial moles of HBr = Molarity × Volume
= 0.15 mol/L × (50.0 mL/1000)
= 0.0075
molInitial moles of KOH = Molarity × Volume
= 0.25 mol/L × (17.0 mL/1000) = 0.00425
sinceNonsense the reaction is a neutralization reaction between a strong acid and a strong base, we can assume that the volume after the reaction would be 50 + 17 = 67 mL or 0.067 L.
The moles of HBr left after reaction = initial moles of HBr - moles of KOH reacted
= 0.0075 - 0.00425= 0.00325 mol
Concentration of HBr after reaction
= Moles of HBr/Volume of solution = 0.00325 mol/0.067
L = 0.0485 MConcentration of H3O+ = Concentration of OH-
= Molarity of KOH added
= 0.25 MSo,
the pH can be calculated using the formula:
pH = -log[H3O+]= -log[0.25]
= 0.602
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when isopropylbenzene (cumene) is treated with nbs and irradiated with uv light, only one product is obtained. propose a mechanism and explain why only one product is formed.
This leads to the formation of p-bromoisopropylbenzene, which is the only product observed in this reaction.
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how can a lack of natural resources and an abundance of natural resources can each cause problems in society
A lack of natural resources can cause problems in society, such as economic instability as industries that rely on those resources become unable to operate.
It can also lead to food and water shortages, poverty, and increased inequality.An abundance of natural resources can also cause problems in society. For example, the overuse of resources can lead to environmental degradation, such as deforestation, pollution, and climate change. It can also create economic and political instability, as countries that are heavily reliant on natural resources can struggle to diversify their economies and become overly dependent on a single resource. Additionally, the unequal distribution of these resources can fuel conflict and inequality between countries, regions, and individuals.
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8. The reaction of hydrogen with chlorine to form gaseous hydrogen chloride is strongly exothermic. From this it can be deduced that A the temperature falls during the reaction. heat is taken in during the reaction. B C more molecules are formed than are used up in the reaction. D hydrogen chloride gas is not easily decomposed by heat.
Answer: The correct option is A) the temperature decreases during the reaction.
Explanation: When hydrogen reacts with chlorine to form hydrochloric acid, the reaction is highly exothermic. This means that the reaction releases energy in the form of heat. The energy released is greater than the energy required to break the bonds in the reactants. Thus, the temperature of the system decreases during the reaction.
Option B is wrong because when heat is absorbed in a reaction, it is an endothermic reaction where energy is absorbed as heat.
Option C is wrong because the number of molecules produced is equal to the number of molecules consumed in the chemical reaction, according to the law of conservation of mass.
Variant D is unrelated to the exothermic nature of the reaction between hydrogen and chlorine leading to the formation of hydrochloric acid. Describes the stability of hydrochloric acid gas unrelated to the statement.
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Find the mole value of 68 liters of O2
68 liters of O₂ at STP is equivalent to 2.693 moles of O₂.
To find the mole value of 68 liters of O₂, we need to use the ideal gas law:
PV = nRT
where P is the pressure of the gas, V is the volume of the gas, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature of the gas.
Assuming that the O₂ is at standard temperature and pressure (STP), which is 0°C and 1 atm, respectively, we can use the following values for the variables in the ideal gas law:
P = 1 atm
V = 68 L
n = ?
R = 0.08206 L·atm/(mol·K)
T = 273 K
Substituting these values into the ideal gas law and solving for n, we get:
n = PV/RT
n = (1 atm) * (68 L) / (0.08206 L·atm/(mol·K) * 273 K)
n = 2.693 moles
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