Question

How much heat is required to heat 5.25 g of water h2o from 5.5?

Answer 1

Heat = mass * heat capacity of water * change in temperature mass = 5.25 g heat capacity of water = 4.186 joule/gram °C Change in temperature = 62.8°C - 5.3°C = 57.5 °C Plug in the values heat = 5.25 g * 4.186 joule/gram °C * 57.5 °C = 1263.6 J Rounded to two three significant figures, it is 1260 J of energy needed. In terms of calories, the heat capacity of water is 1 calorie/gram °C. So do the plugging in all over again. mass = 5.25 g heat capacity of water = 1 calorie/gram °C Change in temperature = 62.8°C - 5.3°C = 57.5 °C heat = 5.25 g * 1 calorie/gram °C * 57.5 °C = 301.9 calories Rounded to 3 significant figures, it is 302 calories Q=SM∆T=4.18*5.25*(62.8-4.3)=1280 J 1280 J * (1 cal/4.18 J) = 307 cal