Chemical Equations and Reactions

The video tutorial from MooMooMath and Science explains chemical equations, detailing the components such as reactants, products, and symbols. It covers the significance of subscripts and coefficients, and the necessity of balancing equations to maintain the conservation of mass. The tutorial also discusses how to indicate the physical states of substances in chemical equations.

What is a chemical reaction?

• A process where substances are mixed without changing their chemical properties.

• A process where substances undergo a chemical change to form new substances.

• A process where substances are dissolved in water.

• A process where substances are physically separated.

In a chemical equation, where are the reactants located?

• Below the arrow.

• On the left side of the arrow.

• Above the arrow.

• On the right side of the arrow.

What does the arrow in a chemical equation signify?

• The amount of reactants used.

• The direction of the reaction.

• The temperature of the reaction.

• The speed of the reaction.

What does the subscript in a chemical formula represent?

• The number of compounds.

• The number of molecules.

• The number of atoms of an element in a molecule.

• The number of moles.

In the chemical formula H2O, what does the '2' indicate?

• Two moles of water.

• Two atoms of oxygen.

• Two atoms of hydrogen.

• Two molecules of water.

What do coefficients in a chemical equation indicate?

• The number of atoms in a molecule.

• The number of protons.

• The number of molecules or moles of each substance.

• The number of electrons.

What is the law of conservation of mass?

• Mass is always increased in a chemical reaction.

• Mass is neither created nor destroyed in a chemical reaction.

• Mass is always decreased in a chemical reaction.

• Mass can be created or destroyed.

Why must a chemical equation be balanced?

• To ensure the reaction occurs faster.

• To ensure the same number of atoms of each element on both sides.

• To ensure the products are more stable.

• To ensure the reactants are completely used up.

What does the symbol 's' represent in a chemical equation?

• Solid

• Aqueous

• Liquid

• Gas

In the chemical equation, what does 'aq' stand for?

• Solid

• Liquid

• Gas

• Dissolved in water