Chem. Sp 21' Final Exam Part 1_Attempt 4

EASIEST question of this exam...what awesome 'Resources' and "Roadmap" should you be using while taking this exam?

• Dr. McQueen's compendium of Iguanas

• I don't need a periodic table! I write at a desk

• The Final Exam "notes packet" and Stoichiometry Roadmap Dr. McQueen has told us to use practically every day since we began reviewing for our final exam!!!!

• I have no idea...

The Thermochemical Equation shown is___________

• Endothermic

• Exothermic

 $q=m\ x\ cp\ x\ \Delta T$  

The specific heat equation is shown above, what does Delta T stand for?

• the heat released or absorbed by a system

• specific heat of a substance

• mass of a substance

• change in temperature

Calculate the enthalpy of reaction (ΔH).

2NO _(g) + O_{2 (g)} → 2NO_{2 (g)}

ΔH_f^o [NO_(g)] = 90.4 kJ

ΔH_f^o [O_2(g)] = 0 kJ

ΔH_f^o [NO_2(g)] = 33.85 kJ

• -113 kJ/mol

• 113 kJ/mol

• -56.5 kJ/mol

• 56.5 kJ/mol

A pot of 2400g of water at a temperature of 25˚C is heated on a stove until the water boils (100˚C). The specific heat of water is 4.18 J/(g˚C).

Determine the heat energy needed to heat the water in the pot to boiling.

• 133.76J

• 43,062.2J

• 752,400J

• 1,003,200J

Ca (s) + ½ O₂ (g) + CO₂ (g) --> CaCO₃ (s)

Using the following information, calculate ΔH for the reaction shown above:

Ca (s) + ½ O₂ (g) --> CaO (s) ΔH = -635.1 kJ

CaCO₃ (s) --> CaO (s) + CO₂ (g) ΔH = 178.3 kJ

• -813.4 kJ

• 592 kJ

• -7687 kJ

• None of these

A 23.7 g piece of iron at 54.9^◦C is cooled and releases 338 J of heat. The specific heat of iron is 0.450 J/g^◦C. What is the final temperature of the iron?

• 31.8 °C

• 13.7 °C

• 23.2 °C

• 27.9 °C

A 15.75-g piece of iron absorbs 1086.75 joules of heat energy, and its temperature changes from 25°C to 175°C. Calculate the specific heat capacity of iron.

• 0.46 J/g^oC

• 1.654 J/g^oC

• 2,567,446.875 J/g^oC

• -0.46 J/g^oC

"Layne" my family's pet bearded dragon has a mass of 405 grams; as he digests his food, he gives off 502.08 (q=-502.8 ) Joules of heat. After his daytime light turns off, his body temperature decreases from 32.2°C to 31.1°C; what is the specific heat of Layne the bearded dragon?

• -0.4 J/g•°C

• -1.13 J/g•°C

• 1.13 J/g•°C

• 0.4 J/g•°C

What does temperature measure?

• Heat of Molecules
• ºC
• Average Kinetic Energy of Molecules
• Thermal Energy