1 A catalyst increases the rate of a reaction by: A Increasing the activation energy B Decreasing the activation energy C Increasing the temperature D Changing the enthalpy change
2 The heat content of a system at constant pressure is called its: A Internal energy B Enthalpy C Entropy D Activation energy
3 According to collision theory, what is necessary for a reaction to occur? A Particles must collide with energy equal to or greater than the activation energy B Particles must collide with low energy C Particles must always be in the same state D Particles must never collide
4 In an energy level diagram for an exothermic reaction, the reactants are at: A Lower energy than products B Higher energy than products C Same energy as products D At zero energy
5 Which of the following is an example of an open system? A A sealed flask containing water B A beaker of water exposed to air C A thermos flask D A closed pressure cooker
6 In an endothermic reaction, heat is: A Released to the surroundings B Absorbed from the surroundings C Neither absorbed nor released D Converted into mass
7 The minimum energy required to start a chemical reaction is called: A Activation energy B Enthalpy change C Bond energy D Kinetic energy
8 Which of the following is an exothermic process? A Melting of ice B Boiling of water C Burning of methane D Photosynthesis
9 What is activation energy? A Energy released during reaction B Minimum energy required for a reaction to occur C Energy of products D Total energy of reactants
11 According to collision theory, which factor increases the rate of a chemical reaction? A Decreasing the temperature B Increasing the activation energy C Adding a catalyst D Reducing the surface area of reactants
12 In an open system, what can be exchanged with the surroundings? A Only energy B Only matter C Both matter and energy D Neither matter nor energy
13 For an exothermic reaction, what is the sign of ΔH? A Positive B Negative C Zero D It depends on the reaction
14 Which instrument is used to measure the heat change during a chemical reaction? A Thermometer B Calorimeter C Barometer D Hydrometer
15 The heat content of a system at constant pressure is called: A Entropy B Enthalpy C Internal energy D Free energy
17 During anaerobic respiration in muscles, glucose is converted into: A Ethanol and CO2 B Lactic acid C CO2 and water D ATP only
18 In an energy level diagram, an exothermic reaction shows products at: A Higher energy than reactants B Lower energy than reactants C Same energy as reactants D Zero energy
19 In the reaction profile of an exothermic reaction, the transition state is: A At the same energy as reactants B At the same energy as products C At a higher energy than both reactants and products D At a lower energy than both reactants and products
20 During anaerobic respiration in yeast, glucose is converted into: A Lactic acid and energy B Ethanol and carbon dioxide C Carbon dioxide and water D Only energy
21 Which of the following is an exothermic reaction? A Melting of ice B Combustion of methane C Evaporation of water D Photosynthesis
22 What is formed at the transition state of a reaction? A Activated complex B Product C Catalyst D Reactant
23 Which of the following is NOT a factor affecting the rate of a reaction? A Temperature B Concentration of reactants C Pressure D Volume of the container
24 In an energy level diagram for an endothermic reaction, the products have: A Lower energy than reactants B Same energy as reactants C Higher energy than reactants D No energy
25 What is the main product of anaerobic respiration in yeast? A Carbon dioxide and water B Lactic acid C Ethanol and carbon dioxide D Glucose and oxygen