Chemical Reactions and Equations Quiz

What do you observe when magnesium ribbon burns?

• It burns with a dazzling light and liberates heat.

• It turns into a liquid.

• It produces a loud sound.

• It does not change.

What happens when zinc granules are added to dilute sulphuric acid?

• No reaction occurs.

• Gas is evolved and the test tube becomes warm.

• It turns into a solid.

• It produces a color change.

What is the product in the reaction of zinc and dilute sulphuric acid?

• Zinc sulphate and hydrogen

• Zinc oxide

• Zinc chloride

• Zinc carbonate

Complete the reaction: Calcium + Chlorine → _____

Which of the following equations is balanced?

• Mg + O2 → MgO

• Zn + H2SO4 → ZnSO4 + H2

• Ca + Cl2 → CaCl2

• H2 + O2 → H2O

How can we make a Chemical Equation more Informative?

• By using (s) for solids, (l) for liquids and (g) for gases.

• By adding more reactants.

• By changing the coefficients.

• By using complex formulas.

What is the significance of a balanced chemical equation?

• It describes the reactants and products.

• It provides quantitative information about the reaction.

• It shows the physical states of the substances.

• It indicates the temperature and pressure.

What is the relationship between the volume of the reactants and the products if all of them are in the gaseous state?

• They are related by small integers.

• They are always equal.

• They depend on the temperature.

• They are inversely proportional.

What should we remember about the quantity of a substance consumed or produced?

• It can be determined only if we use a balanced chemical equation.

• It is always equal to the number of molecules.

• It can be calculated using any equation.

• It is not important in chemical reactions.

What happens if we change the subscripts in formulae of reactants or products during balancing?

• It may change the identity of the substances.

• It will not affect the reaction.

• It will balance the equation.

• It will create new compounds.