Rates & extend of reaction and Chemical Equilibrium

Which one of the following statements are CORRECT definition for the rate of reaction

• The time taken for the reaction to take place

• The speed at which the reaction takes place

• The rate of change in concentration of the products or reactants

• The rate of change in concentration of the products or reactants per unit

• Increase the volume of HCl(aq)

• Increase the temperature of HCl(aq)

• Increase the concentration of HCl(aq)

• Adding more magnesium power

Which ONE of the following statements best describes a state of dynamic equilibrium?

• The limiting reagent has been used up

• The forward and reverse reactions stopped

• The rates of the forward and reverse reactions are equal

• The concentration of products equals the concentration of reactants

The energy change during a chemical reaction is known as …

• bond energy.

• heat of reaction

• activation energy

• activated complex.

Which ONE of the descriptions below is TRUE for a chemical reaction in equilibrium?

• A

• B

• C

• D

• Adding a catalyst.

• Increasing the temperature

• Increasing the pressure by decreasing the volume

• pressure of the gas mixture

• temperature at which equilibrium is reached

• catalyst used

• the reaction has a low concentration of product

• the reaction proceeds at a slow rate

• the reaction has a high concentration of products

• the pH of the solution is below 7

The role of a catalyst in a chemical reaction is to increase the …

• yield.

• activation energy

• heat of reaction

• rate of the reaction.