Quiz Chapter 5: Thermochemistry

1. How does the total energy content of reactants compare to products in an exothermic reaction?

1. Total energy of reactants is higher than products
2. Total energy of reactants is lower than products
3. Total energy of reactants and products are equal
4. Reactants have zero energy content

2. Which statement correctly describes heat flow during an endothermic reaction?

1. Heat flows from the reaction mixture to the surroundings
2. Heat flows from the surroundings into the reaction mixture
3. There is no heat flow between system and surroundings
4. Heat flows only inside the nuclei of atoms

3. What primary branch of science studies heat energy changes during chemical reactions?

1. Electrochemistry
2. Thermochemistry
3. Biochemistry
4. Organic Chemistry

4. Which application is suitable for treating an athlete's acute muscle sprain on the field?

1. Instant hot pack to increase swelling
2. Instant cold pack to reduce pain and swelling
3. Rubbing ethanol to burn the skin surface
4. Applying baking soda and vinegar

5. Which of the following pairs of substances will undergo an exothermic reaction when mixed together?

1. Water and ammonium chloride
2. Water and anhydrous copper(II) sulfate
3. Ethanoic acid and sodium hydrogen carbonate
4. Water and ammonium nitrate

6. When solid sodium hydroxide pellets ($NaOH$) are dissolved in distilled water, what is observed regarding the container temperature?

1. The container becomes noticeably hotter
2. The container becomes noticeably colder
3. The container freezes into ice
4. No temperature change occurs

7. Thermal decomposition of calcium carbonate ($CaCO_3$) requires continuous strong heating. What type of reaction is this?

1. Exothermic reaction
2. Endothermic reaction
3. Displacement reaction
4. Precipitation reaction

8. Why does cellular respiration count as an exothermic reaction?

1. It absorbs carbon dioxide and heat from the environment
2. It breaks down glucose to release energy for body activities
3. It requires sun light to break chemical bonds in blood
4. It converts heat energy into solid carbohydrates

9. When solid ammonium chloride is dissolved in water in a beaker, the beaker feels cold. What type of reaction has occurred?

1. Exothermic reaction
2. Endothermic reaction
3. Neutralisation reaction
4. Combustion reaction

10. Which statement is TRUE regarding the energy profile of an endothermic reaction?

1. The products have lower energy than the reactants
2. The products have higher energy than the reactants
3. Energy level remains flat throughout
4. Reactants contain maximum thermal energy while products have none