If the reaction is endothermic, the sign of H will be negative and the reaction requires added

1. If the reaction is endothermic, the sign of ΔH will be

   		negative and the reaction requires added heat
   		negative and the reaction releases heat
   		positive and the reaction releases heat
   		positive and the reaction requires added heat

2. A sample of a metal at 90.00°C was added to 200.0 g H ₂O at 21.00°C. The temperature rose to 24.50°C. [Specific heat of H ₂O is 4.184 J/(g °C). Specific heat of the metal is 0.949 J/(g°C). How many grams of metal was it?

   		8.05g
   		12.9g
   		47.1 g
   		76.1g
   		23.2g
   		50.0g
   		17.3g
   		30.8g

3. QUESTION 14

4. When 2.45 g of CH₃OCH₃ is burned at constant pressure, 77.42 kJ of heat is given off. What is ∆H for this reaction?
   
   CH₃OCH₃ (l) + 3O₂ (g) --> 2CO₃ (s) + 3H₂O (g) ∆ H _rxn = ?

   		-1460 kJ/mole rxn
   		- 527 kJ/mole rxn
   		2.61 x 10 4 kJ/mole rxn
   		-2480 kJ/mole rxn
   		- 6.16 x 10 2 kJ/mole rxn
   		465 kJ/mole rxn
   		-643 kJ/mole rxn
   		- 37.7 kJ/mole rxn