2. How much heat is required to raise the temperature of 250.0 g of H2O(l) from
10.8 °C to 31.1 °C?
523 kJ
O 274 kJ
21.3 kJ
43.8 kJ
Use the following information to answer the next two questions

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)