Question

1: Select all of factors that affect the rate of a chemical reaction:

	A) activation energy
	B) configuration effectiveness
	C) Frequency of collisions
	D) kinetic energy of colliding particles 2) The initial energy that needs to be supplied to start a chemical reaction is called: A) Heat of reaction B) Activation energy C) Transition state D) Potential energy 3) Select all statements that are correct: A) Chemical reactions are faster when there are more particles of reactants in a small volume B) Chemical reactions are faster when particles of reactants have more space to move through C) Chemical reactions are faster when the average kinetic energy of the particles is higher D) Chemical reactions are faster when the potential energy of the particles is higher 4) Select all statements that are correct: A) During an endothermic process, the surroundings get colder B) In an endothermic process, the potential energy of reactants is higher than the potential energy of the products C) In an exothermic process, energy is released to the environment D) In an exothermic process, potential energy of the reactants is transformed into kinetic energy 5) Which of the following statements is true: A) The rate of chemical reactions does not depend on the complexity of the particles involved B) Chemical reactions are slower when the particles of the reactants are made of smaller molecules C) Chemical reactions are faster when the particles of the reactants are more complex D) Chemical reactions are faster when fewer different reactants are involved

Answer 1

1. factor affect the rate of chemical reaction:
A) Activation energy: If the activation energy of a reaction is high, there are less molecules traveling with that amount of kinetic energy to initiate the reaction, so the rate is less.
B) Frequency of collsion: With an increase in temperature there is an increase in the number of collisions. Increasing the concentration of a reactant increases the frequency of collisionsbetween reactants and will, therefore, increase the reaction rate.
C) kinetic energy of collideing particles:Increasing the temperature of areaction increases the kinetic energyof the particles which increases the number of collisions so the reaction rate increases. ... Smaller reactantparticles provide a greater surface area 1 which increases the chances forparticle collisions so the reaction rateincreases.

2 )) The initial energy that needs to be supplied to start a chemical reaction is called: Activation energy.

3)correct statements

B)Chemical reactions are faster when particles of reactants have more space to move through

C) Chemical reactions are faster when the average kinetic energy of the particles is higher

D) Chemical reactions are faster when the potential energy of the particles is higher.

4)A)During an endothermic process, the surroundings get colder

C)In an exothermic process, energy is released to the environment

D) In an exothermic process, potential energy of the reactants is transformed into kinetic energy

5)A) The rate of chemical reactions does not depend on the complexity of the particles involved

C) Chemical reactions are faster when the particles of the reactants are more complex

D) Chemical reactions are faster when fewer different reactants are involved