Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below. 2Na(s) + 2H,O(1) → 2NAOH(aq) + H, (g) AH=? When 0.0300 mol of Na is added to 100.00 g of water, the temperature of the resulting solution rises from 25.00 °C to 37.90 °C. If the specific heat of the solution is 4.18 J/(g °C), calculate the AH for the reaction, as written.

In a coffee cup calorimeter, 50.0 mL of 0.130 M AGNO, and 50.0 mL of 0.130M HBr are mixed. The following reaction occurs. Ag*(aq) + Br¯(aq) → AgBr(s) If the two solutions are initially at 23.51°C, and if the final temperature is 24.82°C, calculate AH for the reaction in kJ/mol of AgBr formed. Assume a mass of 100.0 g for the combined solution and a specific heat capacity of 4.18 J°C¯1g=1. 84.2 X kJ/mol

2. Calculate the amount of heat required to raise the temperature of 950.0 mL of a solution from 22.5 °C to 38.0 °C if the solution has a density of 1.04 g mL-l and a heat capacity of 4.08 J K-l g. 3. This reaction: CH4(g) + 202(g) → CO2(g) + 2H2O(1) produces 56.0 kJ of heat when 1.00 g of methane is burned. What is the molar heat of combustion for CH4? 4. In thermodynamics heat is represented by the letter 'q' and q is negative for processes which lose heat to the surroundings (i.e. exothermic processes). What is q for burning one mole of methane? 5. What mass of methane would need to be burned in order to generate the heat required to raise the temperature of the solution in question 2? (Hint: look at question 3 for some relevant data) 6. In this lab class you will measure the enthalpy change for hydrochloric acid reacting with sodium hydroxide. What effect, if any, would using nitric acid instead of hydrochloric acid have on the enthalpy changes measured in this experiment? Why?…

4. In a coffee-cup calorimeter, 3.20 g of NH4NO3 is mixed with 86.00 g of water at an initial temperature of 23.53°C. After dissolution of the salt, the final temperature of the calorimeter contents is 21.32°C. Assuming the solution has a heat capacity of 4.184 J/g °C and assuming no heat loss to the calorimeter, calculate the enthalpy change for the dissolution of NH4NO3 in units of kJ/mol.