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?

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

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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)

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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