Bellwork Answer Bank Into endothermic temperature exothermic out ________is a measure of the random motions of the components of a substance When a chemical reaction produces heat it is ___________ and energy flows _____ of the system When a chemical reaction absorbs heat it is ___________ and energy flows _____ the system

Bellwork Answer Bank calorimetry negative endothermic temperature exothermic positive specific heat If energy is flowing out of the system, the reaction is _______ and q is ______. If energy is flowing into the system, the reaction is ______and q is ______. ______is the amount of heat a substance can absorb. _______ is a measure of heat transfer.

Bellwork Please Write: A 65 gram sample of Iron at 100ºC is dropped into 100 ml of water at 21ºC. The final temperature of the mixture is 25ºC. What is the specific heat of Iron? Hint: 1 mL of H2O = 1 gram of H2O The specific heat of water is 4.18J/g•ºC. Use equation: (mwater)(Cpwater)(ΔTwater)= (mmetal)(Cpmetal)(ΔTmetal)

Bellwork Please Write: A 48.5 gram sample of Iron at 100ºC is dropped into 100 ml of water at 21ºC. The final temperature of the mixture is 25ºC. What is the specific heat of Iron? Hint: 1 mL of H2O = 1 gram of H2O The specific heat of water is 4.18J/g•ºC. Use equation: (mwater)(Cpwater)(ΔTwater)= (mmetal)(Cpmetal)(ΔTmetal)

Bellwork Use the diagram above for clarification, please Write: A FRITO chip is burned below 50 mL of water. Before the burning, the Initial temperature of the water is 21ºC. After burning the FRITO, the final temperature of the water is 31ºC. Calculate the amount of heat (q) transferred to the water. Convert Joules to Calories (1000 joules = 0.239 food calories) How many calories are in 1 FRITO? Hint: 1 mL of H2O = 1 gram of H2O The specific heat of water is 4.18J/g•ºC. Use equation: q = (mwater)(Cpwater)(ΔTwater)

Bellwork 2. Consider the following reaction: CaCO3  CaO + CO2 ΔHrxn = +178.4 kJ/mol CaCO3 Is the reaction exothermic or endothermic? If 0.85 mol of CaCO3 decomposes, how much heat is absorbed? 2. Consider the following reaction: CH4 + 2O2  CO2 + 2H2O ΔHrxn = -890.2 kJ/mol CH4 Is the reaction exothermic or endothermic? If 5.8 mol of CH4 is burned, how much heat is released?

Bellwork 1. Consider the following reaction: CO + 2H2  CH3OH ΔHrxn = -90.5 kJ/mol CH3OH How much heat can 60.50 Liters of CO gas produce at STP? Remember: 1 mole of gas at STP = 22.4 liters 2. Consider the highly exothermic thermite reaction below: Fe2O3 + 2Al  Al2O3 + 2Fe ΔHrxn = -853.9 kJ/mol Fe2O3 If 60 grams of Iron Fe2O3 reacts with excess aluminum, how much heat is released.

Bellwork C D 1. In the graph to the right, which letter would be labeled “reactants”? _____ 2. In the graph to the right, which letter would be labeled “products”? ___________ 3. In the graph to the right, which numbered area would be labeled “activation energy”? ___________ 4. In the graph to the right, which letter would be labeled “heat of reaction or ∆H”?? ___________ 5. The reaction to right is would be classified an (circle one: exothermic, endothermic reaction)

Bellwork Answer Bank Increases gas Kinetic 0K or -273Co rapidly Solid decreases 1. Temperature is a measure of the average _____ energy of particles in a sample. 2. When heat is absorbed molecules move more _____ 3. The weakest intermolecular forces exist between particles of a_________ and the strongest intermolecular forces exist between particles of a __________ 4. As a substance is cooled, heat ________ and intermolecular forces _______ 5. At what temperature does molecular motion stop?

Bellwork 1. What is the amount of heat required to raise the temperature of 210.0 g of aluminum by 11.ºC? (specific heat of aluminum = 0.21 cal/gºC) 2. A 7.75g sample of gold is heated using 50.9J of energy. During heating, its temperature changed from 25.0ºC to 81.7ºC. What is gold’s specific heat capacity? 3. From point C to point D, temperature and energy both increase 4. From point D to point E, temperature stays constant and energy increases