A10.0 gram piece of metal is placed in an insulated calorimeter containing 250.0 g of water initially at 20.0°c. if the final temperature of the mixture is 25.0°c, what is the heat change of water?

a) 5230 j
b) −5230 j
c) 209 j
d) −209 j
e) 5440 j

In a laboratory determination of the atomic weight of tin, a sample of tin is weighed in a crucible. nitric acid is added, and the reaction proceeds to give a hydrated tin(iv)oxide plus no2and h2o. the hydrated tin(iv)oxide is then heated strongly and reacts as follows: sno2.xh2o(s)sno2(s)+ xh2o(g)the sno2is finally cooled and weighed in the crucible. explain the effect on the calculated atomic weight of tin that would result from each of the following experimental errors: (a)considerable spattering occurs when the nitric acid is added to the tin.(b)the hydrated tin(iv)oxide is not heated sufficiently to change it completely to tin oxide.