Which of the following are true about catalysts?

Question

1. Catalysts can help to bring the reactants together in the correct orientation
2. The chemical formula of a catalyst is written on the left hand side (reactant) side of an equation.
3. Catalysts can provide a surface on which the reaction occurs.
4. Catalysts increase the activation energy.
5. Catalysts increase the magnitude of the equilibrium constant, thus favoring product formation.
6. "Enzymes" are biochemical catalysts.
7. Catalysts increase the rate of a reaction.
8. Catalysts are slowly used up during the reaction and need to be replaced.

Answer 1

1. Catalysts can help to bring the reactants together in the correct orientation
False. It provides an alternative pathway (of lower activation energy) for reaction to occur.


2. The chemical formula of a catalyst is written on the left hand side (reactant) side of an equation.
False. Written on the arrow that show the reatctants becoming products.


3. Catalysts can provide a surface on which the reaction occurs.
True. For instance platinium in the case of hydrogenation of alkenes.


4. Catalysts increase the activation energy.
False. It LOWERS so reaction occur faster.


5. Catalysts increase the magnitude of the equilibrium constant, thus favoring product formation.
False. Catalysts only increase the rate of attaining the equilibrium. Equilibrium constant is dependable on the temperature at which the reaction occur.


6. "Enzymes" are biochemical catalysts.
True. It's a fact.


7. Catalysts increase the rate of a reaction.
True. That's what catalysts are for.


8. Catalysts are slowly used up during the reaction and need to be replaced.
False. Catalysts will be regenerated after the reaction ends and required in small amount. It's chemical properties will not be change while physical might (change in colour).

Answer 2

1, 3, 5, 6, 7.

2 is incorrect, catalysts are written above the reaction arrow.
4 is incorrect, catalysts decrease the activation energy thus increasing the rate of reaction (see 7)
8 is incorrect, catalysts are not used up (or if they are, they are also regenerated by a different reaction so that they maintain a constant concentration).

edit: about 5, yes i think the answer below is correct, 5 is false actually. catalysts speed up both the forward and the reverse reaction so the equilibrium constant is unchanged. however, 1 is true i think: catalysts can provide a lower energy pathway by way of bringing the reactants together in the correct orientation (rather than random orientations).

Answer 3

(c) rather catalyst varies the path of reaction or u can say mechanism of reaction in which activation potential gets shrink consequently of which fruitful collisions occurred at particularly shrink temperature so better opportunities for molecules to go activation complicated a catalyst is a substance that lowers the activation potential of a chemical reaction yet itself final unchanged during the time of the reaction

Answer 4

1 (I don't know about 2), 3, 5, 6, 8 are true.

Answer 5

7 is definetly true

Answer 6

well 6, and...... 2? maybe 5 ...

Answer 7

1,3,5,6 and 7