Calculate the final temperature when 50.0 mL of water at 65.0 °C are added to 25 mL of water at 25.0 °C.

Idon't understand what to put on the left lines i'm confused can anyone ?

200. ml of 3.00 m nacl solution is diluted to a final volume of 500. ml. what is the molarity of the final solution?

Consider the following reactions. (note: (s) = solid, (l) = liquid, and (g) = gas.) mg(s) + ½o2(g) → mgo(s) + 146 kcal/mole h2(g) + ½o2(g) → h2o(g), δh = -57.82 kcal/mole what type of reaction is represented by the previous two examples?