Chemistry NCFE Review

Front

What happens to a chemical reaction at equilibrium when the concentration of a product is increased?

Back

The reaction shifts to the left, and concentrations of the reactants increase.

Front

What occurs when an electron transitions from a higher energy level to a lower energy level in a hydrogen atom?

Back

Energy is released, and visible light is emitted.

Front

What does a potential energy diagram indicate about the energy required to start a chemical reaction?

Back

It shows the amount of energy needed to initiate the reaction.

Front

How do compounds with metallic bonds compare to ionic compounds in terms of melting points?

Back

Both tend to have high melting points.

Front

In a combustion reaction, what is the significance of balancing the equation?

Back

It ensures the conservation of mass and the correct stoichiometric ratios.

Front

What is the role of a catalyst in a chemical reaction?

Back

A catalyst lowers the activation energy required for the reaction to occur.

Front

What is the definition of a chemical equilibrium?

Back

A state in which the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products.

Front

What is the difference between an endothermic and exothermic reaction?

Back

Endothermic reactions absorb energy, while exothermic reactions release energy.

Front

What is the significance of the coefficients in a balanced chemical equation?

Back

Coefficients indicate the relative amounts of reactants and products involved in the reaction.

Front

What is the definition of a combustion reaction?

Back

A chemical reaction that occurs when a substance reacts with oxygen, producing heat and light.