student has calibrated his/her calorimeter and finds the heat capacity to be 14.2 J/°C. S/he then determines the molar heat capacity of aluminum. The data are: 25.5 g Al at 100.0°C are put into the calorimeter, which contains 99.0 g H2O at 18.6°C. The final temperature comes to 22.7°C. Calculate the heat capacity of Al in J/mol·°C.

Answers

Answer 1

Answer:

Answer:

24.03 J/mol.ºC

Explanation:

For a calorimeter, the heat lost must be equal to the heat gained from water plus the heat gained from calorimeter, which has the same initial temperature as the water.

-Qal = Qw + Qc (minus signal represents that the heat is lost)

-mal*Cal*ΔTal = mw*Cw*ΔTw + Cc*ΔTc

Where m is the mass, C is the specific heat, ΔT is the temperature variation, al is from aluminum. w from water and c from the calorimeter. Cw = 4.186 J/gºC

-25.5*Cal*(22.7 - 100) = 99.0*4.186*(22.7 - 18.6) + 14.2*(22.7 - 18.6)

1971.15Cal = 1699.10 + 58.22

1971.15Cal = 1757.32

Cal = 0.89 J/g.ºC

The molar mass of Al is 27 g/mol

Cal = 0.89 J/g.ºC * 27 g/mol

Cal = 24.03 J/mol.ºC

Related Questions

Which chemical equation below is balanced correctly? 3LiOH + Fe(NO3)3 yields LiNO3 + Fe(OH)3 2NaCl + CaO yields Na2O + CaCl2 Zn + HCl yields ZnCl2 + H2 Mg + HCl yields MgCl2 + H2
Scientists test a hypothesis by?
Which ion is most easily reduced?(l ) Zn2+ (2) Mg2+ (3) Co2+ (4) Ca2+
Which of the following is not an acid-base neutralization reaction? (3 points)NH3 + HCl yields NH4Cl NaOH + CH3COOH yields Na CH3COO + H2O 2HNO3 + Ca(OH)2 yields Ca(NO3)2 + 2H2O H2SO4 + 2NaCl yields 2HCl + Na2SO4
When placed in a freezer, liquid water turns into solid ice. What best describes this change?The water molecules slow down, bonds are broken, and the separated atoms spread out. The water molecules slow down, stronger attractions form between them, and the molecules stop flowing around. The water molecules speed up, attractions between them become weaker, and the molecules spread out. The water molecules speed up, new bonds are formed, and the new molecules are pulled closer together.

What is the IUPAC name for the compound ZnO?

Answers

The IUPAC name for the compound ZnO is zinc oxide.

The International Union of Pure and Applied Chemistry (IUPAC) is responsible for standardizing the naming of chemical compounds to ensure uniformity and clarity in chemical nomenclature. In the IUPAC system, chemical names are based on the elements present in the compound and their respective oxidation states.

In the compound ZnO, "Zn" represents the element zinc, and "O" represents the element oxygen. The oxidation state of zinc in this compound is +2, and the oxidation state of oxygen is -2. To form a neutral compound, one zinc ion (Zn²⁺) combines with one oxide ion (O²⁻) in a 1:1 ratio. Therefore, the IUPAC name for the compound ZnO is "zinc oxide."

Zinc oxide is a white powder that is commonly used in various applications, such as in the production of rubber, ceramics, and cosmetics. It is also used as a pigment in paints and as an additive in food products. The IUPAC naming system ensures that scientists and chemists worldwide can communicate effectively about chemical compounds and their properties.

To learn more about IUPAC name, here

brainly.com/question/33646537

#SPJ6

it's
Zn=Zinc
and O=Oxide
so it will be Zinc Oxide

In chemistry class, Allen determined the effectiveness of various metals in releasing hydrogen gas from hydrochloric acid. Several weeks later, Allen read that a utilities company was burying lead next to iron pipes to prevent rusting. Allen hypothesized that less rusting would occur with the more active metals. He placed the following into 4 separate beakers of water: (a) 1 iron nail, (b) 1 iron nail wrapped with an aluminum strip, (c) 1 iron nail wrapped with a magnesium strip, and (d) 1 iron nail wrapped with a lead strip. He used the same amount of water, equal amounts (mass) of the metals, and the same type of iron nails. At the end of 5 days, he rated the amount of rusting as small, moderate, or large. He also recorded the color of the water. What is the independent variable?a) the amount of water
b) the metals strips
c) amount of rust
d) hydrochloric acid

Answers

Answer:

b) the metals strips

Explanation:

In an experimental design, an independent variable is a variable that is changed or manipulated in a series of experiments. An independent variable is not dependent on any other variable in the experiment. The hypothesis for this experiment is stated to be: "If the chemical activity of the metallic wrapper is increased, then less rusting of iron will occur. The independent variable relates to the type of metal wrapping strip, and the dependent variables are the amount of rusting and color of the water.

Identify the atom oxidized, the atom reduced, the oxidizing agent, and the reducing agent. 2Fe + 3V2O3 -------> Fe2O3 + 6VO

Answers

In the given reaction, Fe is the reducing agent and V is the oxidizing agent.

What is a reducing agent?

An atom or compound that loses its electrons to other substances in a reduction-oxidation reaction and gets oxidized to a higher valency state is called a reducing agent.

A reducing agent can be defined as one of the reactants of a redox reaction that reduces the other reactant by giving its electrons to the reactant. If the reducing agent can not give away its electrons to others in a reaction, then the reduction reaction cannot occur.

Given, the following chemical reaction:

2Fe + 3V₂O₃ → Fe₂O₃ + 6VO

The V₂O₃ oxidation state of V:

2 x + 3(-2) = 0

2x = 6

x = + 3

The Fe₂O₃ oxidation state of Fe:

2 y + 3 (-2) = 0

2y = 6

y = + 3

The V acts as an oxidizing agent because it accepts one electron to change the oxidation state from +3 to +2.

Fe acts as a reducing agent because it gives out its electrons to change the oxidation state from 0 to +3.

Learn more about reducing agent, here:

brainly.com/question/2890416

#SPJ2

Explanation:

Fe- reducing agent (since it is oxidized to fe203)

v203- oxidizing agent(since it is reduced)

Which structural adaptation would help a plant survive better in a shady environment? A.
thorns

B.
small leaves

C.
large leaves

D.
brightly colored flowers