Energy and rates of reactions

Dissolving salt in water causes the temperature of the water to go down. Is this outcome best described as endergonic or exergonic?

• Endergonic

• Exergonic

Is the following chemical equation best described as endergonic or exergonic?

4 Fe + 3 O₂ + 6 H₂O → 4 Fe(OH)₃ + Energy

• Endergonic

• Exergonic

Is the following chemical equation best described as endergonic or exergonic?

6 H₂O + 6 CO₂ + Energy → C₆H₁₂O₆ + 6 O₂

• exothermic

• endothermic

• endergonic

• catabolic

The reaction of propane with oxygen produces carbon dioxide, water, and energy. The energy released is primarily thermal, but some light energy is also produced. Is this reaction best classified as endergonic, endothermic, exergonic, or exothermic?

• endergonic

• endothermic

• exergonic

• exothermic

True or False. The reaction rate of a chemical reaction can be described as the rate at which products are consumed.

• True

• False

The Collision Model states that particles must collide in order to _____?

• bounce

• conserve energy

• react

• multiply forces

True or False. According to the law of conservation of energy, it is possible to release more energy from a reaction than the sum of the energy originally held in the bonds of the reactants and the activation energy used to start the reaction.

• True

• False

Calculate the percentage mass of carbon in the chemical formula C₃H₈. Carbon has an atomic mass of 12.011 amu and hydrogen has an atomic mass of 1.007 amu. Round your answer to the nearest whole number.

• 80%

• 81%

• 82%

• 83%

True or False. As a catalyst speeds up the reaction rate of a chemical reaction, the catalyst is consumed in order to speed the rate up.

• True

• False

True or False. In order for a chemical reaction to occur the energy in the chemical bonds of the reactants must be broken by an input of energy.

• True

• False