Every system in the body is made from atoms, molecules, cells, tissues, and organs. These building blocks all work together to allow you to grow, obtain energy, move, stay healthy, and reproduce. Each system provides a different function to support life. Which of the following is a control system in the body?
Circulatory
Reproductive
Nervous
Muscular
Answer:
THE RIGHT ONE IS THE NERVOUS SYSTEM
Explanation:
THE EXPLANATION IS THAT : The nervous system is the part of an animal's body that coordinates its behavior and transmits signals between different body areas. In vertebrates it consists of two main parts, called the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS contains the brain and spinal cord.
Please help me fill in the blanks
Answer: ew i hate science but ive done that same thing before i dont remember the answers though
Explanation:
Please help ASAP!!
Explain why a pond at 18 °C has more thermal energy than a cup of boiling water at
100 °C.
Answer:
The pond has more energy because I is so much larger that the Cup of boiling water. Since that mass of the pond is so much larger, It is generating more energy than a boiling cup of water.
The form of energy carried by moving electrical charges is ____________________ energy.
Answer:
kinetic
Explanation:
hope this helps
Answer:
Kinetic energy
Explanation:
The amount of water (density 1.00 g mL-1) in grams that must be added to 26.2 g of
MgCl2 in the preparation of a 1.5 % by mass solution is:
Answer:
1720.8g water are necessaries
Explanation:
Mass percent is defined as the mass of solute (In this case, MgCl2) in 100g of solution (Mass MgCl2 + Mass water). To solve this question we must find the mass of solution that we need to produce th 1.5% by mass solution. Thus, we can find the mass of water that we need as follows:
Mass solution:
26.2g MgCl2 * (100g Solution / 1.5g MgCl2) = 1747g solution
Mass water:
1747g solution - 26.2g MgCl2 = 1720.8g water are necessaries
If a photon dropping from the n = 7 to the n = 1 level hit the surface of Au, what would be the wavelength of the ejected electron in nanometers?
Answer:
here's the answer.hope it helps
The table shows the thickness, top density, and bottom
density of the different layers of the Earth.
Which statement is supported by the information in the
table?
Thickness
(km)
Density
(g/cm)
Top Bottom
Types of Rock
Found
As depth increases, the density of the layers increases.
As depth increases, the density of the layers decreases.
As depth increases, the thickness of the layers
increases.
As depth increases, the thickness of the layers
decreases.
Crust
30
2.2
2.9
Silicic rocks
720
3.4
4.4
Upper
mantle
Peridotite
2,171
4.4
Lower
mantle
5.6
Magnesium and
silicon oxides
Outer
2,259
9.9
12.2
Iron+oxygen
core
1,221
12.8
13.1
Inner
core
Iron+oxygen
Se
[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]
As depth increases, the density of the layers decreases.
Thanks.Hope it helps.The statement, that describes the thickness, top density, and bottom density of the different layers of the Earth is "as depth increases, the density of the layers decreases."
What is density layers of Earth?The density of the Earth's inner layers determines their order. The densest layer is the solid metal inner core, the mantle is of intermediate density, and the lithosphere, particularly the continental lithosphere, is the least dense layer.
Pressure rises as you go deeper. Mass/volume = density. As a result, as the volume drops, so does the density. Because of pressure, the strata beneath us become extremely dense. As a result, as the depth of the earth increases, so does the density.
Hence the correct answer is as depth increases, the density of the layers decreases.
Learn more about density layers of Earth here
https://brainly.in/question/1197257
#SPJ2
PLEASE HELP 15 POINTS!! Which equation is needed to solve this problem?
Answer:
Option 1
Explanation:
The question is asking us what formula is used to obtain the quantity of heat added to a given mass of mercury in order to cause its temperature to change.
This quantity of heat is obtained from;
q = mcspΔT
Where;
q = quantity of heat added
m = mass of the mercury
csp= specific heat capacity of mercury
ΔT = temperature change
Under the right conditions aluminum will react with chlorine to produce aluminum chloride.
2 Al + 3 Cl2 - 2 AICI3
How many grams of aluminum are needed to react completely with 11.727 liters of chlorine?
CORRECT ANSWER IS 9.42, but what are the steps to get that answer ?
Answer:
9.42 g
Explanation:
Step 1: Write the balanced equation
2 Al + 3 Cl₂ ⇒ 2 AICI₃
Step 2: Calculate the moles corresponding to 11.727 L of Cl₂
Since the conditions are not specified, we will assume Cl₂ is at standard temperature and pressure. At STP, 1 mole of Cl₂ occupies 22.4 L.
11.727 L × 1 mol/22.4 L = 0.524 mol
Step 3: Calculate the moles of Al needed to react with 0.524 moles of Cl₂
The molar ratio of Al to Cl₂ is 2:3. The moles of Al needed are 2/3 × 0.524 mol = 0.349 mol
Step 4: Calculate the mass corresponding to 0.349 moles of Al
The molar mass of Al is 26.98 g/mol.
0.349 mol × 26.98 g/mol = 9.42 g
A sample of 4.0 L of nitrogen, at 1.2 atmospheres, is transferred to a 12 L container.
What will the pressure be in the new container?
Answer:
The pressure will be 0.4 atm.
Explanation:
The gas laws are a set of chemical and physical laws that allow determining the behavior of gases in a closed system. The parameters evaluated in these laws are pressure, volume, temperature and moles.
As the volume increases, the gas particles (atoms or molecules) take longer to reach the walls of the container and therefore collide with them less times per unit of time. This means that the pressure will be lower because it represents the frequency of collisions of the gas against the walls. In this way pressure and volume are related, determining Boyle's law which says:
"The volume occupied by a certain gaseous mass at constant temperature is inversely proportional to pressure"
Boyle's law is expressed mathematically as:
P*V= k
If you initially have the gas at a volume V1 and press P1, when the conditions change to a volume V2 and pressure P2, the following is satisfied:
P1*V1= P2*V2
In this case:
P1= 1.2 atmV1= 4 LP2= ?V2= 12 LReplacing:
1.2 atm* 4 L= P2* 12 L
Solving:
[tex]P2=\frac{1.2 atm*4 L}{12 L}[/tex]
P2= 0.4 atm
The pressure will be 0.4 atm.
the enthaply of formation of water is -285.8kj/mol. what can be inferred from this statement
Answer: It takes 285.8 kJ of energy to form one mole of water
Explanation:
The enthalpy of formation of a substance is the change in enthalpy that occurs when a substance is formed from its elements in their standard states. The enthalpy of the formation of water is -285.8 kJ/mol, which means that it takes 285.8 kJ of energy to form one mole of water from its elements (hydrogen and oxygen) under standard conditions. This value is negative, which means that the formation of water releases energy. This is why water is often referred to as an "exothermic" substance because it releases energy when it is formed. The negative value of the enthalpy of formation for water can be explained by the fact that the bonds formed between hydrogen and oxygen atoms in water are stronger than the bonds between hydrogen and oxygen atoms in the individual elements. This means that it takes less energy to break the bonds in the elements than it releases when the bonds in water are formed, resulting in a net release of energy.
For more information about Enthalpy;
https://brainly.com/question/11317028
Answer:
This means that 285.8 kJ/mol is evolved when one mole of water is formed.
What is the enthalpy of formation?
The term enthalpy of formation has to do with the energy that is released or absorbed when a molecule of water if formed from its constituents.
The fact that the enthalpy of formation of water is -285.8 kJ/mol implies that 285.8 kJ/mol is evolved when one mole of water is formed.
Explanation:
4. A student poured 50 cm^3
water into a beaker and
measured the water's
temperature. The student added
1.00 g calcium chloride to the
water, stirred the mixture and
then recorded the temperature.
The concentration of a calcium
chloride solution is 12 g/dm^3.
Calculate the volume of this
solution, in cm^3, that contains
9.0 g of calcium chloride.
Answer:
V = 750 cm³
Explanation:
The volume of the solution can be calculated by the following formula:
[tex]V = \frac{M}{C}[/tex]
where,
V = Volume of solution = ?
M = Mass of Calcium Chloride = 9 g
C = Concentration of Solution = 12 g/dm³
Therefore,
[tex]V = \frac{9\ g}{12\ g/dm^3}\\\\V = (0.75 dm^3)(\frac{1000\ cm^3}{1\ dm^3})[/tex]
V = 750 cm³
A graduated cylinder contains 50.0 ml of water. A 23.5 g piece of unknown metal is carefully dropped into the cylinder. When
the metal is completely covered with water, the water rises to the 53.4 ml mark. What is the density of the unknown piece of
metal in g/ml?
To find the density of the unknown piece of metal, we can use the formula:
Density = mass / volume.
How to find the density ?The volume of the metal can be calculated by deducting the starting water volume (50.0 ml) from the final water volume (53.4 ml) after the metal is introduced. We know the mass of the unknown metal is 23.5 g.Volume of metal = 53.4 ml - 50.0 ml = 3.4 ml.Now we can substitute the values into the density formula: Density = 23.5 g / 3.4 ml = 6.9 g/ml.Therefore, the density of the unknown piece of metal is 6.9 g/ml.To know more about density , check out :
https://brainly.com/question/1354972
#SPJ1
9. a) What is an isotope?
Answer:
Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element. Hope this helps, have a good day! :)
Answer:
atoms with the same number of protons and electrons but different numbers of neutrons
Explanation:
5. 16.3 g of NaCl is dissolved in water to make 1.75 L of solution. What is the molarity of this solution? A 0.159 M B 0.278 M C 9.31 M D 33.4 M
Answer: The molarity of this solution is 0.159 M.
Explanation:
Given: Mass of solute = 16.3 g
Volume = 1.75 L
Number of moles is defined as the mass of substance divided by its molar mass.
Hence, moles of NaCl (molar mass = 58.44 g/mol) ar calculated as follows.
[tex]Moles = \frac{mass}{molar mass}\\= \frac{16.3 g}{58.44 g/mol}\\= 0.278 mol[/tex]
Molarity is the number of moles of a substance present in a liter of solution.
So, molarity of the given solution is calculated as follows.
[tex]Molarity = \frac{no. of moles}{Volume (in L)}\\= \frac{0.278 mol}{1.75}\\= 0.159 M[/tex]
Thus, we can conclude that the molarity of this solution is 0.159 M.
Why does the standard model of the universe need to be change?
Explanation:
The standard model of particle physics is a relativistic theory of quantum fields developed between 1970 and 1973 [citation needed] based on the ideas of unification and symmetries [1] that describes the fundamental structure of matter and vacuum considering the elementary particles as irreducible entities whose kinematics is governed by the four known fundamental interactions (except for gravity, whose main theory, general relativity, does not fit the mathematical models of the quantum world). The word "model" in the name comes from the 1970s when there was not enough experimental evidence to confirm the model. [1] To date, almost all experimental tests of the three forces described by the standard model are in agreement. with their predictions. However, the standard model falls short of being a complete theory of fundamental interactions due to several unresolved issues.
The half-life of carbon-14 is 5715 years. How long would it take for 100 grams to decay to
12.5 grams
We are given:
half-life of carbon = 5715 years
Initial mass = 100 grams
Final mass = 12.5 grams
Finding the time taken:
Number of half-lives:
We know that in the relation:
[tex]\frac{Final\_mass}{Initial\_mass} = \frac{1}{2^{n}}[/tex], n is the number of half-lives taken
replacing the given values:
12.5 / 100 = 1/2ⁿ
1/8 = 1/2ⁿ
2ⁿ = 8
2ⁿ = 2³
n = 3
Hence, it took 3 half-lives to reduce the mass to 12.5 grams
Number of years:
Time taken = 3 half-lives
we know that one half-life is 5715 years, replacing that value:
Time taken = 3*(5715) years
Time taken = 17145 years
Therefore, after 17145 years, a 100 gram sample of carbon will decay and only 12.5 grams will remain
How many moles of NaCl would you have in 100 mL of this solution?
Answer:
You didnt give me a molarity so ill show you how to solve it with an equation
Explanation:
Molarity represent by M
M= mols/ Volume (in liters)
so mols = (whatever the molarity was) x (.100L because it is =100ml)
Mols= M x (.100)
plug in the molarity you have for x and you are done
9)
Which solution will have the highest concentration of solute particles?
A) 0.50 M NaCl
B) 1,00 M CaCl2
C) 2.00 M sodium ions
D) 2.50 M C6H1206
Answer: The answer is B) 1.00 M CaCl2
Explanation: I just did it on usatestprep and it said it was correct .
Identify the Precipitation Reaction Below:
A) CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g)
B) H2SO4(aq) + 2 LiOH(aq) → 2 H2O(l) + Li2SO4(aq)
C) Mg(s) + Cu(NO3)2(aq) → Mg(NO3)2(aq) + Cu(s)
D) HCl(aq) + (NH4)2S(aq) → H2S(g) + 2 NH4Cl(aq)
E) NaCl(aq) + AgNO3(aq) → AgCl(s) + NaNO3(aq)
Answer:
(E)
Explanation:
When aqueous solutions are added together, one of the products is s solid.
Which statement is true about a reversible reaction? (5 points)
The forward and reverse reactions stop.
The product is a salt and the reactant is an acid.
The products react to re-form the original reactants.
The forward reaction continues but reverse reaction stops.
Answer:
C: The products react to re-form the original reactants.
Explanation:
A reversible reaction is one where the conversion of reactants to products as well as the conversion of products to reactants happen at the same time.
What this means is that the products of the reaction could react to reform the initial reactants.
Thus, option C is the correct answer.
Answer:
C
Explanation:
The products react to re-form the original reactants.
Which phase change results in atoms with the highest kinetic energy? A. Boiling B. Melting C. Freezing D. Condensing
Answer: Boiling because it makes the molecules in water bounce around.
Hope it helps.
5. (a-c) In the balanced equation below, how many grams of solid iron can be formed if 50.0g Fe2O3 reacts with 10.0g of CO?
Fe2O3(s) + 3CO(g) → 2Fe(s) +3CO2
a. What mass of the excess reactant remains after the reaction occurred?
b. If you conducted an experiment and 11.5 grams of Fe(s) was formed what would be the percent yield?
c. If the percent yield for the process to obtain 75 kg of CO2 was 80.7%, how many kg of CO is needed?
From the balanced equation of the reaction, the mole ratio of the reactants is 1:3.
Mole of 50.0 g [tex]Fe_2O_3[/tex] = 50/160 = 0.3125 mol
Mole of 10.0 g CO = 10/28 = 0.3571 mol
Stoichiometric equivalent of [tex]Fe_2O_3[/tex] = 0.3571/3 = 0.1190 mol
In other words, [tex]Fe_2O_3[/tex] is in excess.
Excess mole = 0.3125 - 0.1190 = 0.1935 mol
Mass of 0.1935 mol [tex]Fe_2O_3[/tex] = 0.1935 x 160 = 30.96 grams
Mole ratio of CO to Fe = 3:2
Equivalent mole of Fe that would be formed = 0.3571 x 2/3
= 0.2381 mol
Mass of 0.238 mol Fe = 0.238 x 56 = 13.328 grams
Percent yield of Fe = 11.5/13.328 x 100 = 86.28%
Mole of 75 gk CO2 = 75000/44 = 1704.55 mol
Mole ratio of CO2 and Co = 1:1
Equivalent mole of CO = 1704.55 mol
Mass of 1704.55 mol CO = 1704.55 x 28 = 47.73 kg
80.7% = 47.73 kg
100% = 100 x 47.73/80.7
= 59.14 kg
In other words, 59.14 kg of CO would be needed.
More on stoichiometric problems can be found here: https://brainly.com/question/29856106
#SPJ1
what is van't hoff factor?
state the formulas to calculate " i " during association or dissociation.
tysm! :)
The relationship between the calculated concentration of a material and the actual concentration of particles is known as the Van't Hoff factor.
I is the difference between a typical or theoretical colligative quality and an observable one.
What does the connection van t Hoff factor mean?The van 't Hoff factor is the difference between the concentration of a material determined by its mass and the concentration of particles actually formed when the substance is dissolved. The van 't Hoff factor is virtually 1 for the majority of non-electrolytes dissolved in water.
What does Van t Hoff factor mean in terms of connection and dissociation?For dissociation, association, and the non-electrolyte solute, the Van't Hoff factor value is more than one, less than one, and equal to one respectively.
to know more about concentration visit :-
https://brainly.com/question/12970323
#SPJ1
A 752g sample of an unknown substance has its temperature increase by 8°C after being exposed to 1287.424 j,calculate the specific heat of
the substance. _____J/g*C (3 sig figs)
Answer:
0.214 J/g.°C
Explanation:
Step 1: Given data
Mass of the sample (m): 752 gTemperature increase (ΔT): 8 °CProvided heat (Q): 1287.424 JStep 2: Calculate the specific heat of the substance (c)
The specific heat of the substance is an intrinsic property of a substance. We can calculate it using the following expression.
Q = c × m × ΔT
c = Q / m × ΔT
c = 1287.424 J / 752 g × 8 °C = 0.214 J/g.°C
Starting with 2.50 mol of N2 gas (assumed to be ideal) in a cylinder at 1.00 atm and 20.0C, a chemist first heats the gas at constant volume, adding 1.36 * 104 J of heat, then continues heating and allows the gas to expand at constant pressure to twice its original volume. Calculate (a) the final temperature of the gas; (b) the amount of work done by the gas; (c) the amount of heat added to the gas while it was expanding; (d) the change in internal energy of the gas for the whole process.
Answer:
a) [tex]T_b=590.775k[/tex]
b) [tex]W_t=1.08*10^4J[/tex]
d) [tex]Q=3.778*10^4J[/tex]
d) [tex]\triangle V=4.058*10^4J[/tex]
Explanation:
From the question we are told that:
Moles of N2 [tex]n=2.50[/tex]
Atmospheric pressure [tex]P=100atm[/tex]
Temperature [tex]t=20 \textdegree C[/tex]
[tex]t = 20+273[/tex]
[tex]t = 293k[/tex]
Initial heat [tex]Q=1.36 * 10^4 J[/tex]
a)
Generally the equation for change in temperature is mathematically given by
[tex]\triangle T=\frac{Q}{N*C_v}[/tex]
Where
[tex]C_v=Heat\ Capacity \approx 20.76 J/mol/K[/tex]
[tex]T_b-T_a=\frac{1.36 * 10^4 J}{2.5*20.76 }[/tex]
[tex]T_b-293k=297.775[/tex]
[tex]T_b=590.775k[/tex]
b)
Generally the equation for ideal gas is mathematically given by
[tex]PV=nRT[/tex]
For v double
[tex]T_c=2*590.775k[/tex]
[tex]T_c=1181.55k[/tex]
Therefore
[tex]PV=Wbc[/tex]
[tex]Wbc=(2.20)(8.314)(1181_590.778)[/tex]
[tex]Wbc=10805.7J[/tex]
Total Work-done [tex]W_t[/tex]
[tex]W_t=Wab+Wbc[/tex]
[tex]W_t=0+1.08*10^4[/tex]
[tex]W_t=1.08*10^4J[/tex]
c)
Generally the equation for amount of heat added is mathematically given by
[tex]Q=nC_p\triangle T[/tex]
[tex]Q=2.20*2907*(1181.55-590.775)\\[/tex]
[tex]Q=3.778*10^4J[/tex]
d)
Generally the equation for change in internal energy of the gas is mathematically given by
[tex]\triangle V=nC_v \triangle T[/tex]
[tex]\triangle V=2.20*20.76*(1181.55-293)k[/tex]
[tex]\triangle V=4.058*10^4J[/tex]
How many moles of magnesium atoms react with 1 mole of oxygen molecules?
1 mole of magnesium atoms will react with 2 moles of oxygen molecules. This is because the chemical equation for the reaction between magnesium and oxygen is: Mg + O2 → MgO.
What is chemical equation?A chemical equation is a symbolic representation of a chemical reaction, showing the reactants (starting materials) on the left side and the products (resulting substances) on the right side. The symbols used to represent the reactants and products are chemical formulas, which use the symbols of the elements in the reaction. The arrow between the reactants and products indicates the type of reaction taking place. The coefficients next to the symbols and formulae of entities indicate the number of moles of each species that are involved in the reaction. The overall reaction is balanced when the number of atoms of each element on the left side of the equation is equal to the number of atoms of that element on the right side of the equation.
This equation shows that for every 1 mole of magnesium atoms, 2 moles of oxygen molecules are required for the reaction to take place. Therefore, 1 mole of magnesium atoms will react with 2 moles of oxygen molecules.
To learn more about chemical equation
https://brainly.com/question/13847161
#SPJ1
Compressing a spring increases its
a.kinetic energy
b.potential energy
c.electrical energy
d.chemical energy
Answer:
B. potential energy
Explanation:
Potential energy ( Mechanical in this case ) is energy stored by force. so If you are compressing a spring you are increasing more potential to it by force.
Explain the phenomenon of diffussion.
Answer:
the movement of particles from a higher consentration to a lower consentration through a mechanical support.
Explanation:
Suppose two materials: (1) titanium and (2) a new synthetic polymer are tested by hanging a mass from a test sample made from each material. Both samples have an initial length of and a cross-section area of . The synthetic polymer is know to behave similarly to the Kelvin-Voigt model, and has parameters and . Use MATLAB to plot the deformation in each specimen for the first ten seconds of the test. Neglect the mass of each test specimen, and assume that the hanging mass is instantly applied to each material at time .
Answer:
ffffffffffffff
Explanation:
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv