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Ok, I've figured them out except for #5, 11, 14, & 16. #14 & 16 are the same principal, Q1+Q2=0 , but my equations just arent working out. Someone, anyone, help me set these up. Please!!

So, 1790 kJ x Cal/4.18J = 428. Cal Got that one. I need help with number 14. I realize I need to use c=Q/mT m= 9.85g delta T= -98.6 degrees C I need help finding Q. Can I just look up the Q in the book as H2O(s) ?

Id greatly appreciate it!! I mean, I ahve a few ideas, it's just that webassign isnt accepting my answers, so Im obviously doing SOMETHING wrong..

1. A 5 inch piece of cake provides 1790 kJ of energy. What is this in Calories? 5. Mercury has a freezing point of -38.8 degrees Celsius. How much heat energy (in joules) must be released by Hg if 1.40mL is cooled from 23.0 degrees Celsius to -38.8 degrees Celsius and then frozen to a solid? (The density of Hg is 13.6 g/cm3, its specific heat is 0.140 J/g – K and its heat of fusion is 11.4 J/g.) 8. Using the following reactions, calculate the enthalpy change for the formation of PbO(s) from Pb(s) and O(g). Pb(s) + CO(g) -> PbO(s) + C(s) H= -106.8 kJ 2 C(s) + O2(g) -> 2 CO(g) H= -221.0 kJ Pb(s) + O2(g) -> PbO(s) H= ? kJ 9. You wish to know the enthalpy change for the formation of PCl3(l) based on the equations below. If 1.10 mol of PCl3(l) from phosphorus and chlorine. P4(s) + 6 Cl2(g) -> 4 PCl3(l) H= ? kJ P4(s) + 10 Cl2(g) -> 4 PCl5(s) H= -1774.0 kJ PCl3(l) + Cl2(g) -> PCl5(s) H= -123.8 kJ 11. CaO is mixed with H2O to give Ca(OH)2, which reacted with CO2 to give limestone. Ca(OH)2(s) + CO2(g) -> CaCO3(s) + H2O(g) (a) Calculate the enthalpy change (:umno: What quantity of heat is evolved or absorbed if 2.30 kg of Ca(OH)2 is allowed to react with a stoichiometric amount of CO2? 14. A 9.85g piece of metal is heated to 98.6 degrees Celsius and then the temperature drops to 0.0 degrees Celsius, it is found that 0.43g of ice melted. What is the metal’s specific heat? 16. Suppose you add 100.0g of H2O at 65.0 degrees Celsius to 100.0g of ice at 0.0 degrees Celsius. The water cools to 0.0 degrees Celsius. When the ice and water temperature get to a uniform temperature of 0.0 degrees Celsius, how much ice has melted? Im not asking for answers, Im just asking how to setup the problems. I've already failed the test, I just want to understand these concepts for the final. Help me out, anyone, please!! :hihi:

My name is Tyler, Im a Freshmen college student, and taking CHEM 1211. I'll be around here from time to time to help w/ Chemistry homework, and also to get help!! Hope you guys can steer me in the right direction & that I can help on a few of the easier problems :umno: