Answer:
1. D; 2. A; 3. A; 4. C; 5. A; 6. C; 7. C; 8. D; 9. A; 10. B; 11. C; 12. D; 13. B; 14.B
Explanation:
1. Without the presence of enzymes in cells, the reactions in living things would occur too slowly or require temperatures that are too high for cells to survive. Enzymes are catalysts in living organisms also called as bio catalysts. They speed up the reaction by lowering the activation energy.
2. Its heat which provides the activation energy needed to start the fire. The three main components of fire triangle are heat, fuel and oxygen.
3. Rate of chemical reaction depends upon temperature with maximum rate at optimum temperature, beyond the optimum temperature the enzyme might get denatured lowering the rate of reaction.
4. Inhibitors are the one which reduce the rate of chemical reaction. There are some which are competitive inhibitors of substrate and some which are non-competitive inhibitors (do not bind at active site as substrate).
5. When two liquids are mixed in an endothermic reaction, the temperature of the solution gets colder. Endothermic reaction needs energy for the reaction to occur where as exothermic reaction liberates out energy during the chemical reaction.
6. In any reaction requires any outside source of energy such as heat then it is called endothermic reaction.
7. The best form of fire safety is fire prevention.
8. If the amount of energy released is more than the energy utilized in the reaction then it is called exothermic reaction.
9. Enzymes are also called as bio catalyst. They speed up the reaction living organisms.
10. The reaction between oxygen and a fuel is called combustion reaction.
11. When larger pieces are broken down into smaller pieces then the surface area increases for the action of digestive enzymes upon them.
12. The purpose of the burning splint in a reaction is to provide activation energy
13. Heating the reaction flask will provide the activation energy to begin a reaction.
14. Oxygen supports the burning of candle so if the candle is covered by a beaker the flame will go out once all the oxygen inside is used up.
