Chemical Reactions

To increase the yield of the products

To increase the total kinetic energy of the reactants

To be consumed so that the reaction can proceed faster

To provide an alternative pathway with a lower activation energy ($E_a$)

It decreases the activation energy of the reaction

Particles move faster and collide more frequently with more energy

The enthalpy change of the reaction becomes more exothermic

The concentration of the reacting particles increases

Decreasing the concentration of $HCl$

Using a larger flask for the reaction

Using powdered $CaCO_3$ instead of large marble chips

Decreasing the temperature of the acid

The equilibrium shifts to the right, increasing the yield of C.

The equilibrium shifts to the left, decreasing the yield of C.

The reaction rate decreases for both forward and reverse reactions.

The concentration of C remains unchanged.

To increase the yield of ammonia produced.

To increase the rate at which equilibrium is reached.

To shift the equilibrium position to the right.

To allow the reaction to occur at a lower pressure.

The solid turns from pink to blue.

The solid turns from blue to pink.

The solid turns from pink to colorless.

The solid turns from green to blue.

$Mg + 2e^{-} \rightarrow Mg^{2+}$

$Mg^{2+} + 2e^{-} \rightarrow Mg$

$Mg \rightarrow Mg^{2+} + 2e^{-}$

$Mg^{2+} \rightarrow Mg + 2e^{-}$

The oxidation state increases.

The oxidation state decreases.

The oxidation state remains unchanged.

The oxidation state always becomes zero.

$CuO$

$Cu$

$H_{2}$

$H_{2}O$