4th Heat Test Review

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

• - 418 J

• 209 J

• 83 J

• 418 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

If 200 grams of water is to be heated from 24.0° C to  100.0° C to make a cup of tea, what is the mass and what is the change in temperature?

• m=100g,  ∆t= 224 C
• m=200g,  ∆t=124 C
• m=100g,  ∆t=24 C
• m=200g,  ∆t=76 C

How many Joules of energy are required to make 100 grams of ice at 0 ^οC completely melt? The specific latent heat of fusion of ice is 334 J/g

• 200 J

• 400 J

• 33,400 J

• 2,000,000 J

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

How much energy is required to heat up 12kg of copper from 10 °C to 120 °C. The specific heat capacity is 390 J/kg °C.

• 46800 J
• 561600 J
• 514800 J

How many Joules of energy are required to make 0.1 kg of ice at 0 ^οC completely melt? The heat of fusion of ice is 334000 J/kg

• 200 J
• 400 J
• 33,400 J
• 2,000,000 J

Calculate the amount of energy required to melt 35.0 grams of ice.
 H_f = 80.0 cal/g,  H_v = 560.0 cal/g, S_H = 1.00 cal/g ºC

• 19,600 cal
• 35.0 cal
• 2,800 cal 
• 1,568,000 cal 

Between which points is the temperature of the substance increasing?

• A-B only. 
• A-B, C-D, E-F
• B-C only. 
• B-C, D-E

Bond making is

• Endothermic

• Exothermic