Name:___________________________________________ Date:_____________ Pd:_______#:_______
Chemical Equations… in Your Own Words!
2 Na + Cl2 → 2 NaCl
sodium chloride
Two atoms of sodium (Na) REACT with one molecule of chlorine (Cl2) to
PRODUCE 2 molecules of sodium chloride (NaCl).
For each chemical equation below, write what is happening in the reaction as
a sentence! Use your periodic table and the example above to help you!
1. Zn + 2HCl → ZnCl2 + H2
hydrochloric acid
zinc chloride
2. Cl2(g) + 2NaBr(aq) → 2NaCl(aq) + Br2(l)
sodium bromide
sodium chloride
Did You Know?
(g) = gas
(l) = liquid
(s) = solid
(aq) = aqueous solution
(dissolved in water)
3. HCl(aq) + FeS(s) → FeCl2(aq) + H2S(g)
hydrochloric acid
iron sulfide
iron chloride
hydrogen sulfide
4. CaCO3(s) + 2 HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)
calcium carbonate
hydrochloric acid
calcium chloride
carbon dioxide
water
What’s a “Balanced” Chemical Equation?
The following are balanced equations. Count the numbers of atoms of each element in the
reactants and the products. What do you notice is always true in balanced equations?
__________________________________________________________________________
Na + Cl2
→
2 NaCl
_____ Na atoms
_____ Na atoms
_____ Cl atoms
_____ Cl atoms
2 C4H10 + 13 O2
→
8 CO2 + 10 H2O
_____ C atoms
_____ C atoms
_____ H atoms
_____ H atoms
_____ O atoms
_____ O atoms
MgO + H2O
→
Mg(OH)2
_____ Mg atoms
_____ Mg atoms
_____ O atoms
_____ O atoms
_____ H atoms
_____ H atoms
Fe(s) + CuSO4(aq)
→
FeSO4(aq) + Cu(s)
_____ Fe atoms
_____ Fe atoms
_____ Cu atoms
_____ Cu atoms
_____ S atoms
_____ S atoms
_____ O atoms
_____ O atoms
The substances on the left side in an equation are the _____________________
and the substances on the right side of the equation are __________________!
The following is an UNBALANCED equation. What makes it unbalanced?
N2 + 3H2 → NH3
_____ N atoms
_____ N atoms
_____ H atoms
_____ H atoms