A chemical reaction is run in which 513 Joules of heat are absorbed and the internal energy changes by +1234 Joules. Calculate "w" for the system.

If 200 kJ of energy are evolved in a reaction, is this reaction endothermic or exothermic and what is the value of "q"?

Does this image depict an exothermic or endothermic reaction

Which energy diagram, A or B, depicts a reaction with a positive value of H?

What is the energy change when the temperature of 13.6 grams of gaseous nitrogen is decreased from 31.2 C to 23.2 C?

Specific heat of nitrogen: 1.04 J/g*C

When a sample of gaseous nitrogen is heated, 313 Joules of energy are added to a 12.4 gram sample and the final temperature is 24.7 C. What is the initial temperature of the nitrogen?

Specific heat of nitrogen: 1.04 J/g*C

A 47 gram aluminum spoon (specific heat 0.88 J/g*C ) at 29 C is placed in 185 grams of water (specific heat 4.184 J/g*C) at 90 C and the temperature of the two become equal. What is the final temperature when the two become equal?

A 70 gram copper fork (specific heat 0.386 J/g*C ) at 20 C is placed in 170 grams of water (specific heat 4.184 J/g*C ) at 80 C and the temperature of the two become equal. What is the final temperature when the two become equal?

During an experiment, the teacher discovers that it takes 240 Joules to increase the temperature of 12.0 grams of solid aluminum from 25.4 C to 40.1 C. Calculate the specific heat of aluminum from her experiment.

How many Joules are needed to heat 463 grams of liquid water from 0 C to 100 C?

Specific heat capacity of water: 4.184 J/g*C

How many Joules are required to heat 120 grams of water from 20 C to 130 C?

Specific heat of water: 4.184 J/g*C

Specific heat of steam: 2.02 J/g*C

Heat of vaporization: 2260 J/g

How many Joules are released by the water when the temperature of 15.0 grams is changed from 20.0 C to 10.0 C?

Specific heat of water: 4.184 J/g*C

How many kJ are required to heat 80 grams of water from -40C to 150C ?

Specific heat of ice: 2.06 J/g*C

Heat of fusion: 334 J/g

Specific heat of water: 4.184 J/g*C

Heat of vaporization: 2260 J/g

Specific heat of water vapor: 2.02 J/g*C

CH4(g) + 2O2(g) --> CO2(g) + 2H2O(g)

Calculate the standard enthalpy of reaction and is the reaction exothermic or endothermic.

Standard enthalpies:

CH4: -75 kJ/mol

O2: 0 kJ/mol

CO2: -394 kJ/mol

H2O: -284 kJ/mol

2NO(g) + O2(g) --> 2NO2(g)

Calculate the enthalpy of formation and if the reaction is endothermic or exothermic.

Enthalpies of formation:

O2(g): 0 kJ/mol

NO(g): 90.25 kJ/mol

NO2(g): 33.18 kJ/mol

2H2(g) + O2 --> 2H2O(g)

Using the average bond enthalpies below, calculate the change in enthalpy.

H--H : 436 kJ/mol

O2 : 495 kJ/mol

O--H : 463 kJ/mol

CH4(g) + Cl2(g) --> CH3Cl(g) + HCl(g)

Using the average bond enthalpies below, calculate the change in enthalpy.

C--H: 413 kJ/mol

Cl--Cl : 242 kJ/mol

C--Cl : 328 kJ/mol

H--Cl : 431 kJ/mol

The standard enthalpy for the reaction below is 940 kJ at 298 K.

TiO2(s)--> Ti(s) + O2(g)

What is the standard enthalpy change at 298 K for the reaction below?

2Ti(s) + 2O2(g) --> 2TiO2(s)

The standard enthalpy change at 298 K for the reaction below is 92.2 kJ.

2NH3(g)--> N2(g) +3 H2(g)

What is the standard enthalpy change at 298 K for the reaction below?

1/2 N2(g) + 3/2 H2(g) --> NH3(g)

(1.) 2HgO(s) --> 2Hg(l) + O2(g) {standard enthalpy is 181.6 kJ}

(2.) HgCl2(s) --> Hg(l) + Cl2(g) {standard enthalpy is 224.3 kJ}

What is the standard enthalpy change for the reaction below?

(3.) 2HgCl2(s) + O2(g) --> 2HgO(s) + 2Cl2(g)

(1.) 2PbO(s) --> 2Pb(s) + O2(g) {standard enthalpy change is 434.6 kJ}

(2.) 2Zn(s) + O2(g) --> 2ZnO(s) {standard enthalpy change is -696.6 kJ}

What is the standard enthalpy change for the reaction below?

(3.) PbO(s) + Zn(s) --> Pb(s) + ZnO(s)

Which image (A, B, or C) depicts the system with the greatest average kinetic energy?

True or False : The colder the temperature, the lower the average kinetic energy.

True or False : At thermal equilibrium, the average kinetic energy of both bodies are the same, so the temperatures of both bodies are the same.