Exothermic and Endothermic Reactions

Chemistry ⇒ Chemical Reactions and Equations

Exothermic and Endothermic Reactions starts at 8 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Exothermic and Endothermic Reactions. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 12

A chemical reaction absorbs 50 kJ of heat from the surroundings. Is this reaction exothermic or endothermic?

A chemical reaction has ΔH = +75 kJ/mol. Is this reaction exothermic or endothermic?

A reaction has ΔH = -120 kJ/mol. What does the negative sign indicate about the reaction?

A student mixes barium hydroxide and ammonium chloride in a beaker. The beaker becomes very cold. What type of reaction is this?

A student observes that the temperature of a solution increases when a chemical is added. What type of reaction is likely occurring?

Describe the energy changes that occur during the combustion of methane.

Describe the energy changes that occur during the melting of ice.

Describe what happens to the temperature of the surroundings during an exothermic reaction.

Explain the difference between exothermic and endothermic reactions in terms of energy transfer.

Explain why photosynthesis is considered an endothermic reaction.

Explain why the dissolution of some salts in water is endothermic while for others it is exothermic.

Is the combustion of hydrogen gas an exothermic or endothermic reaction?

Is the neutralization reaction between hydrochloric acid and sodium hydroxide exothermic or endothermic?

Is the process of dissolving potassium nitrate in water exothermic or endothermic?

Is the process of melting ice endothermic or exothermic?

Is the process of sublimation of dry ice (solid CO₂) exothermic or endothermic?

Is the reaction of zinc with dilute sulfuric acid exothermic or endothermic?

The decomposition of calcium carbonate (CaCO₃) into calcium oxide (CaO) and carbon dioxide (CO₂) is an example of which type of reaction?

When water freezes, is the process exothermic or endothermic?

A reaction has an activation energy of 150 kJ/mol and releases 80 kJ/mol of energy overall. Is the reaction exothermic or endothermic? Justify your answer.