Balancing Chemical Equations

Front

What is a chemical equation?

Back

A chemical equation is a symbolic representation of a chemical reaction, showing the reactants and products along with their quantities.

Front

What does it mean to balance a chemical equation?

Back

Balancing a chemical equation means ensuring that the number of atoms for each element is the same on both sides of the equation.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; the total mass of reactants equals the total mass of products.

Front

How many atoms are in a molecule of MgCl2?

Back

A molecule of MgCl2 contains 1 magnesium atom and 2 chlorine atoms.

Front

What is the coefficient in a chemical equation?

Back

A coefficient is a number placed in front of a chemical formula in an equation to indicate how many molecules or moles of that substance are involved.

Front

How do you determine the number of atoms in a compound?

Back

To determine the number of atoms in a compound, multiply the subscript of each element by the coefficient in front of the compound.

Front

What is the balanced equation for the reaction of hydrogen and chlorine to form hydrochloric acid?

Back

The balanced equation is H2 + Cl2 → 2HCl.

Front

How do you balance the equation: H2 + O2 → H2O?

Back

The balanced equation is 2H2 + O2 → 2H2O.

Front

What is the balanced equation for the decomposition of mercury(II) oxide?

Back

The balanced equation is 2HgO → 2Hg + O2.

Front

How many hydrogen atoms are in 4H2O?

Back

There are 8 hydrogen atoms in 4H2O.