Question

19. How much heat is liberated (in kJ) from 2.47E+2 g of silver
when it cools from 8.86E+1 °C to 2.57E+1 °C? The heat capacity of
silver is 0.235 J g^{-1} °C^{-1} *g*−1°*C*−1. Note,
"heat liberated" implies that the change in heat is negative. Enter
a positive number

20. A sample of sand initially at 2.18E+1 °C absorbs 1.386E+3 J
of heat. The final temperature of the sand is 6.7E+1 °C. What is
the mass (in g) of sand in the sample? The heat capacity of sand is
0.84 J g^{-1} °C^{-1}*g*−1°*C*−1.

21. 1.13E+1 ounces of water are heated during the preparation of a cup of coffee. 1.186E+3 J of heat are added to the water, which is initially at 1.96E+1 °C. What is the final temperature of the coffee?

38. A sample of copper absorbs 4.28E+1 kJ of heat, resulting in a temperature rise of 6.86E+1 °C. Determine the mass (in kg) of the copper sample if the specific heat capacity of copper is 0.385 J/g°C.

39. A 5.51E+1 g sample of water at 9.979E+1 °C is placed in a constant pressure calorimeter. Then, 2.31E+1 g of zinc metal at 2.19E+1 °C is added to the water and the temperature drops to 9.61E+1 °C. What is the specific heat capacity of the zinc metal measured in this experiment?

40. A 2.61E+1 g sample of aluminum at 1.009E+2 °C is added to 1.001E+2 g of water at 2.23E+1 °C in a constant pressure calorimeter. What is the final temperature of the water in °C? The specific heat capacity of aluminum is 0.903 J/g°C .

43. Copper (Cu) pellets with a mass of 2.71E+1 g at 9.970E+1 °C are placed in a constant pressure calorimeter of negligible heat capacity containing 1.07E+2 mL of water. The temperature of the water rises from 2.19E+1 °C to 2.31E+1 °C. What is the specific heat capacity of the copper pellets?

In scientific notation.

44. When 1.03E-1 g of Zn(s) combines with 5.86E+1 mL of HCl(aq) in a coffee cup calorimeter, all of the zinc reacts, which increases the temperature of the HCl solution from 2.31E+1 °C to 2.49E+1 °C: Zn(s) + 2HCl(aq) → ZnCl_22 (aq) + H_22 (g)

Calculate the enthalpy change of the reaction
ΔH_{rxn}*r**x**n* in J/mol. (Assume the volume
of the solution doesn't change, density of the solution is 1.00
g/mL and the specific heat capacity of the solution is 4.184
J/g°C.) Answer in scientific notation.

48. What is the enthalpy of formation
(\DeltaΔ*H*^{\circ}∘_f*f* ) of NaHCO_33 (s) from its
constituent elements.

49. Use standard enthalpies of formation to calculate the standard enthalpy of reaction for the following reaction:

2 H_22 S(g) + 3 O_22 (g) → 2 H_22 O(l) + 2 SO_22 (g)
\DeltaΔ*H*^{\circ}∘_{rxn}*r**x**n*

ALL ANSWERS MUST BE IN SCIENTIFIC NOTATION.

Answer #1

1. The specific heat of iron metal is 0.450 J/g⋅K. How many J of
heat are necessary to raise the temperature of a 1.05 −kg block of
iron from 28.0 ∘Cto 85.0 ∘C?
2. A 1.80-g sample of phenol (C6H5OH) was burned in a bomb
calorimeter whose total heat capacity is 11.66 kJ/∘C. The
temperature of the calorimeter plus contents increased from
21.36∘Cto 26.37∘C.
A. Write a balanced chemical equation for the bomb calorimeter
reaction.
B. What is the heat...

The enthalpy change for the dissolution of NH4NO3 is +26.8
kJ/mol. When 40.0 g of NH4NO3 dissolves in 250.0 g of water in a
coffee cup calorimeter, what will the final temperature of a
solution be if it was initially at 25.0 °C? Assume that the heat
capacity of the solution is the same as the specific heat of pure
water, 4.184 J/(g·K). Hint: don't forget to add the masses of
solute and solvent.

Calorimetry Problem: Show your work neatly and methodically.
Include the sign associated with ΔH.
1. When a 6.55 gram sample of solid sodium hydroxide dissolves
in 115.00 grams of water in a coffee-cup calorimeter, the
temperature rises from 21.6°C to 38.7°C. Calculate ΔH, in kJ/mole
NaOH, for the solution process. NaOH(s) Na1+(aq) + OH1- (aq) The
specific heat of the solution is 4.18 J/g °C. 3.
2, A 2.600 gram sample of phenol, C6H5OH, was burned in a bomb...

When 0.100 g Zn(s) combines with enough HCl to make a total of
55.0 mL solution in a coffee cup calorimeter, all of the zinc
reacts, which increases the temperature of the HCl solution from
23.0∘C to 24.5 ∘C: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) Calculate
the enthalpy change of the reaction ΔHrxn. (Assume the density of
the solution is 1.00 g/mL and the specific heat capacity of
solution is 4.184 J/g∘C.) in J/mol. (Enter answer in numerical form...

When 0.109 g of Zn(s) combines with enough HCl to make 55.7 mL
of HCl(aq) in a coffee cup calorimeter, all of the zinc reacts,
which increases the temperature of the HCl solution from 23.2 °C to
24.8 °C: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) Calculate the
enthalpy change of the reaction ΔHrxn in J/mol. Insert your answer
in kJ, but do not write kJ after the number. (Assume the density of
the solution is 1.00 g/mL and the...

When 0.113 g of Zn(s) combines with enough HCl to make 53.6 mL
of HCl(aq) in a coffee cup calorimeter, all of the zinc reacts,
which increases the temperature of the HCl solution from 23.3 °C to
24.7 °C: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) Calculate the
enthalpy change of the reaction ΔHrxn
in J/mol. Insert your answer in kJ, but do not write kJ after the
number. (Assume the density of the solution is 1.00 g/mL and the...

When a solid dissolves in water, heat may be evolved or
absorbed. The heat of dissolution
(dissolving) can be determined using a coffee cup
calorimeter.
In the laboratory a general chemistry student finds that when
18.53 g of
Cs2SO4(s) are dissolved in
100.40 g of water, the temperature of the solution
drops from 25.54 to
22.92 °C.
The heat capacity of the calorimeter (sometimes referred to as the
calorimeter constant) was determined in a separate
experiment to be 1.85 J/°C....

When a solid dissolves in water, heat may be evolved or
absorbed. The heat of dissolution (dissolving) can be determined
using a coffee cup calorimeter. In the laboratory a general
chemistry student finds that when 4.13 g of CuCl2(s) are dissolved
in 111.70 g of water, the temperature of the solution increases
from 25.33 to 28.58 °C. The heat capacity of the calorimeter
(sometimes referred to as the calorimeter constant) was determined
in a separate experiment to be 1.89 J/°C....

When 0.500 g CaO(s) is added to 140. g H2O at 23.1 °C in a
coffee cup calorimeter, this reaction occurs.
CaO(s)+H2O(l)-->Ca(OH)2 (aq) and enthalpy = -81.9 kj/mol
Calculate the final temperature of the solution. The specific
heat capacity of water is 4.184

Zinc metal reacts with hydrochloric acid according to the
following balanced equation. Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g) When
0.119 g of Zn(s) is combined with enough HCl to make 53.4 mL of
solution in a coffee-cup calorimeter, all of the zinc reacts,
raising the temperature of the solution from 21.7 ∘C to 24.5 ∘C.
Part A Find ΔHrxn for this reaction as written. (Use 1.0 g/mL for
the density of the solution and 4.18 J/g⋅∘C as the specific heat
capacity.)

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 5 minutes ago

asked 20 minutes ago

asked 22 minutes ago

asked 22 minutes ago

asked 31 minutes ago

asked 31 minutes ago

asked 36 minutes ago

asked 38 minutes ago

asked 39 minutes ago

asked 39 minutes ago

asked 41 minutes ago

asked 57 minutes ago