a. Calculate the energy transferred when the temperature of 75 cm³ of water rises from 23 °C to 54 °C.

b. When 8 g of sodium chloride is dissolved in 40 cm³ of water the temperature falls from 22 °C to 20.5 °C. Calculate the energy absorbed by the solution when sodium chloride dissolves.

c. A student added 50 cm³ of sodium hydroxide to 50 cm³ of hydrochloric acid. Both solutions were at 18 °C to start with. When the solutions were mixed a reaction occurred. The temperature rose to 33 °C. Calculate the energy released in this reaction.