Answer:
a) Ca (s) + 2 H₂O (l) ---> Ca(OH)₂ (aq) + H₂ (g)
b) Al₂O₃ (s) + 3 C (s) + 3 Cl₂ (g) ---> 2 AICI₃ (s) + 3 CO (g)
c) 2 FeCl₃ (aq) + 3 H₂S (g) ---> Fe₂S₃ (s) + 6 HCI (aq)
d) CaCO₃ (s) + 2 HCI (aq) ---> CaCl₂ (aq) + CO₂ (g) + H₂O (l)
Explanation:
For an equation to be balanced, there must be an equal amount of each type of atom on both sides of the reaction. The reactants are on the left side and the products are on the right side.
a) ------------------------------------------------------------------------------------------------------
The unbalanced equation:
Ca (s) + H₂O (l) ---> Ca(OH)₂ (aq) + H₂ (g)
<u>Reactants</u>: 1 calcium, 2 hydrogen, 1 oxygen
<u>Products</u>: 1 calcium, 4 hydrogen, 2 oxygen
The balanced equation:
Ca (s) + 2 H₂O (l) ---> Ca(OH)₂ (aq) + H₂ (g)
<u>Reactants</u>: 1 calcium, 4 hydrogen, 2 oxygen
<u>Products</u>: 1 calcium, 4 hydrogen, 2 oxygen
b) ------------------------------------------------------------------------------------------------------
The unbalanced equation:
Al₂O₃ (s) + C (s) + Cl₂ (g) ---> AICI₃ (s) + CO (g)
<u>Reactants</u>: 2 aluminum, 3 oxygen, 1 carbon, 2 chlorine
<u>Products</u>: 1 aluminum, 1 oxygen, 1 carbon, 3 chlorine
The balanced equation:
Al₂O₃ (s) + 3 C (s) + 3 Cl₂ (g) ---> 2 AICI₃ (s) + 3 CO (g)
<u>Reactants</u>: 2 aluminum, 3 oxygen, 3 carbon, 6 chlorine
<u>Products</u>: 2 aluminum, 3 oxygen, 3 carbon, 6 chlorine
c) ------------------------------------------------------------------------------------------------------
The unbalanced equation:
FeCl₃ (aq) + H₂S (g) ---> Fe₂S₃ (s) + HCI (aq)
<u>Reactants</u>: 1 iron, 3 chlorine, 2 hydrogen, 1 sulfur
<u>Products</u>: 2 iron, 1 chlorine, 1 hydrogen, 3 sulfur
The balanced equation:
2 FeCl₃ (aq) + 3 H₂S (g) ---> Fe₂S₃ (s) + 6 HCI (aq)
<u>Reactants</u>: 2 iron, 6 chlorine, 6 hydrogen, 3 sulfur
<u>Products</u>: 2 iron, 6 chlorine, 6 chlorine, 3 sulfur
d) ------------------------------------------------------------------------------------------------------
The unbalanced equation:
CaCO₃ (s) + HCI (aq) ---> CaCl₂ (aq) + CO₂ (g) + H₂O (l)
<u>Reactants</u>: 1 calcium, 1 carbon, 3 oxygen, 1 hydrogen, 1 chlorine
<u>Products</u>: 1 calcium, 1 carbon, 3 oxygen, 2 hydrogen, 2 chlorine
The balanced equation:
CaCO₃ (s) + 2 HCI (aq) ---> CaCl₂ (aq) + CO₂ (g) + H₂O (l)
<u>Reactants</u>: 1 calcium, 1 carbon, 3 oxygen, 2 hydrogen, 2 chlorine
<u>Products</u>: 1 calcium, 1 carbon, 3 oxygen, 2 hydrogen, 2 chlorine