Chapter 15 Review

What  is the formula to calculate heat energy required to raise the temperature of any substance?

• Q = m Cp ∆T
• Q = m Cp
• Q =  ½ m v
• m = Q Cp

If the specific heat of water is 4,186 J/kg∙°C, how much heat is required to increase the temperature of 1.2 kg of water from 23 °C to 39 °C? 

• -80,371.2 J
• 44,938.6 J
• 80,371.2 J
• 112,575.9 K

A sample of iron receives 50.J of heat energy that raises the temperature of the iron 25.0°C. If iron has a specific heat of  0.10 J/g°C, what is the mass of the iron sample?

• 25 g
• 30 g
• 20 g
• 50 g

The specific heat is the amount of energy needed to raise the temperature one degree Celsius of 1 gram of a substance.

• True
• False

The specific heat(c) of copper is 0.39 J/g °C. What is the temperature change(∆t) when 100 Joules of heat(Q) is added to 20 grams?

• 12.82 °C
• 24.12°C
• 351 °C

You have 20 g of water with specific heat of 4.18 J/gŸ°C.  The temperature changes from 25° C to 20° C.  How much heat energy (Q) moves from the water to the surroundings?

• 418 Joules
• 209 J
• 83 J
• 4.18 J

The temperature of an unknown piece of metal with a mass of 30.00 g changes from 25.0 °C to 35.0 °C when the metal absorbs 350.0 J of energy. What is the specific heat of the metal?

• 1.17 J/g°C
• -1.17 J/g°C
• 0.857 J/g°C
• -0.857 J/g°C

Given the thermochemical equation, calculate the heat evolved when 74.6 g of sulfur dioxide (molar mass = 64.07 g/mol) is converted to sulfur dioxide.

• -115 kJ

• 115 kJ

• -115.39 kJ

• 115.39 kJ

Using the thermochemical eq. given, calculate the heat evolved when 266 g of white phosphorus burns in air.

• -6.47 x 10^3 kJ

• -6468 kJ

• 6.47 x 10^3 kJ

• 6468 kJ

The reaction:

A + B → C

ΔH = + 25 kJ

is a(n):

• Exothermic Reaction

• Endothermic Reaction

• Neutralization Reaction

• Spontaneous Reaction