unit 8 Thermochem

What is the unit conversion between calories and joules?

• 1 cal = 4.18 J

• 1 cal = 3.14 J

• 1 cal = 4.00 J

• 1 cal = 4.50 J

In an endothermic reaction, where is heat written in the chemical equation?

• On the left side of the arrow

• On the right side of the arrow

• Above the arrow

• Below the arrow

Which of the following factors does NOT increase the reaction rate?

• Decreasing temperature

• Mixing

• Increasing surface area

• Increasing concentration

What is the specific heat capacity of iron in the given example?

• 0.15 cal/g°C

• 1.00 cal/g°C

• 0.50 cal/g°C

• 0.25 cal/g°C

Which phase change represents the transition from solid to gas?

• Sublimation

• Melting

• Condensation

• Freezing

What are 2 factors that increase reaction rate?

In your own words, describe the math behind calculating the energy change of a chemical reaction? What are the steps?

In the reaction 2 H2 + O2 --> 2 H2O ; calculate the energy produced from Hydrogen gas if we have a change in heat as +1405.8 kJ / mol and we start with 4.25 moles of hydrogen. Round to 2 decimal places.

What is fusion and what is vaporization in your own words? (HINT: Fusion and melting are the same thing)

How much energy is required to melt 2.9 grams of ice into water? (Fusion energy is 6.01 and vaporization energy is 40.56) Round to 3 decimal places