balancing equations

Front

What is a balanced equation?

Back

A balanced equation has the same number of each type of atom on both sides of the equation, indicating that mass is conserved during a chemical reaction.

Front

How do you determine the number of hydrogen atoms in a compound like 3(NH₄)₂CrO₄?

Back

Multiply the number of NH₄ groups (2) by the number of hydrogen atoms in each (4), then multiply by 3: 3 x 2 x 4 = 24 hydrogen atoms.

Front

Which of the following is a balanced equation: PbO₂ + 2H₂ → H₂SO₄ or 2Na + 2H₂O → 2NaOH + H?

Back

2Na + 2H₂O → 2NaOH + H is balanced.

Front

What does it mean to balance a chemical equation?

Back

Balancing a chemical equation means adjusting the coefficients in front of compounds to ensure that the number of atoms for each element is the same on both sides.

Front

What is the coefficient in a chemical equation?

Back

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

Front

How do you balance the equation Mg + Cl₂ → MgCl₂?

Back

This equation is already balanced as there is 1 magnesium atom and 2 chlorine atoms on both sides.

Front

What is the balanced form of the equation PCl₅ + _ H₂O → _ HCl + H₃PO₄?

Back

The balanced form is PCl₅ + 4 H₂O → 5 HCl + H₃PO₄.

Front

What is the balanced form of the equation Zn + _ HCl → _ ZnCl₂ + _ H₂?

Back

The balanced form is Zn + 2 HCl → ZnCl₂ + H₂.

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; it is conserved.

Front

What is a reactant in a chemical reaction?

Back

A reactant is a substance that undergoes change during a chemical reaction, found on the left side of the equation.