How much energy is required to increase the temperature of 25 g water from 0 C∘ to 50 C∘. The specific heat capacity of water is 1 cal/g⋅c∘   (Hint: Specific heat Q and 1 cal = 4.2J)

A 20-g ice cube floats in 180 g of water in a 100-g copper cup; all are at a temperature of 0°C. A piece of lead at 90°C is dropped into the cup, and the final equilibrium temperature is 12°C. What is the mass of the lead? (The heat of fusion and specific heat of water are 3.33  105 J/kg and 4,186 J/kg · °C, respectively. The specific heat of lead and copper are 128 and 387 J/kg · °C, respectively.)

If 31.0 g of milk at a temperature of 4.05°C is added to a 260-g cup of coffee at a temperature 91.0°C, what is the final temperature of the mixture? Assume coffee has a specific heat of 4.19 ✕ 103 J/(kg · K) and milk has a specific heat of 3.93 ✕ 103 J/(kg · K).

Suppose you want to raise the temperature of a 0.185-kg piece of ice from -20.0°C to 130°C. The heat of fusion is Lf = 334 kJ/kg, and the heat of vaporization is Lv = 2256 kJ/kg. In this problem, take 1520 J/kg⋅°C as the specific heat of steam, and 2090 J/kg⋅°C as the specific heat of ice.  Part (a)  How much heat, in kilocalories, must be transferred for this to happen, including the energy needed for phase changes?   Part (b)  How much time, in seconds, is required to do this, assuming a constant 20.0 kJ/s rate of heat transfer?