0.155 mol of a solid was dissolved in 330 mL of water at 21.5 oC. After the solid had fully dissolved, the final temperature of the solution was 15.9 oC. What is the molar heat of solution of the substance

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.