A sample of octane (C8H18) that has a mass of 0.750 g is burned in a bomb calorimeter. As a result, the temperature of the calorimeter increases from 21.0°C to 41.0°C. The specific heat of the calorimeter is 1.50 J/(g • °C), and its mass is 1.00 kg. How much heat is released during the combustion of this sample? Use . 22.5 J 30.0 J 31.5 J 61.5 J

Explanation:

mass, m = 1 kg

specific heat, c = 1.5 J/g°C

rise in temperature, ΔT = 41 - 21 = 20

heat released, H = m x c x ΔT

H = 1 x 1.5 x 1000 x 20

H = 30,000 J

H = 30 kJ.

the device is called “ rocket engine”

the temperature in kelvin of 2.0 dm3 of an ideal gas is doubled and its pressure is increased by a factor of four. what is the final volume of the gas