CHEMICAL EQUATIONS

In chemical equation,the number of atoms of each element on both sides of the equation must be the same.

• TRUE

• FALSE

In chemical equation, name of product must be write on left-hand side meanwhile name of reactant on right-hand side.

• TRUE

• FALSE

Which one is correct chemical equations for following reactions :

nitrogen gas + hydrogen gas → ammonia gas

• N₂ (s) + 3H₂ (g) → 2NH₃ (g)

• N₂ (g)+ 4H₂ (g) → 2NH₄ (g)

• N₂ (g) + 3H₂ (g) → 2NH₃ (g)

• N₂ (g) + H₂ (g)→ NH₃ (g)

Which one is correct chemical equations for following reactions :

sodium metal + water → aqueous solution of sodium hydroxide + hydrogen gas

• 2Na + 2H₂O → 2NaOH +H₂

• 2Na(s) + 2H₂O(l) → 2NaOH (aq) +H₂ (g)

• Na₂(s) + (H₂O)₂(l) → 2NaOH(aq) +H₂ (g)

• 2NaOH (aq) +H₂ (g) → 2Na(s) + 2H₂O(l)

Which one is correct chemical equations for following reactions :

Solid copper(II) carbonate decomposes into solid copper (II) oxide and carbon dioxide gas when heated.

copper(II) carbonate → copper (II) oxide + carbon dioxide gas

• CuCO₃ (s) → CuO (s) +

  Δ

  CO₂ (g)

• CuCO₃ (s) → CuO (s) +

  CO₂ (g)

• CuCO₃ → CuO +

  Δ

  CO₂

• CuCO₃ (s) → CuO (s) +

  Δ

  CO₂ (s)

Which one is correct chemical equations for following reactions :

Burning of aluminium powder in excess oxygen produces white aluminium oxide powder.

aluminium + oxygen → aluminium oxide

• 4Al + 3O₂ → 2Al₂O₃

• 2Al(s) + 3O₂(g) → Al₂O₃ (s)

• 4Al(s) + 3O₂(g) → 2Al₂O₃ (s)

• 4Al(s) + 3O₂(g) → 2Al₃O₂ (s)

Chemical equation can be balanced by adjusting the number of ________ infront of chemical formula

• mol

• coefficient

• subscripts