Suppose you heat a metal object with a mass of 30.9 g to 96.0 oC and transfer it to a calorimeter containing 100.0 g of water at 18.1 oC. The water and metal reach a final temperature of 23.3 oC. What is the specific heat of the metal in J/g-oC?

Answer is: the equilibrium  shifts toward the reactants, to the left side of chemical reaction.it is because lead(ii) nitrate dissociates in water: pb(no₃)₂ → pb²⁺(aq) + 2no₃⁻(aq).according to lechatelier's principle, the position of equilibrium moves to counteract thechange (more lead cations, common ion), the position of equilibrium will move so that the concentration ofproducts decrease and concentration of reactants of chemical reaction increase.read more on -

Ithink the correct answer is 3

Burned piece of steel wool does not gain mass. so only d could be true.

Needs for population