1) neatly & clearly complete the following equations: (4 marks each)\nsodium oxide + water → sodium…

1) neatly & clearly complete the following equations: (4 marks each)\nsodium oxide + water → sodium hydroxide_(aq)\nskeleton:\nbalanced:\n\niron (iii) + hydrofluoric acid → hydrogen gas + iron (iii) fluoride_(aq)\nskeleton:\nbalanced:\n\nsulfuric acid + barium hydroxide_(aq) → water + barium sulfate_(s)\nskeleton:\nbalanced:\n\n2) balance the following chemical equations: (2 marks each)\nc_3h_8(g) + o_2(g) → co_2(g) + h_2o(g)\nbacl_2(aq) + k_3po_4(aq) → kcl(aq) + ba_3(po_4)_2(s)
Answer
Explanation:
Step1: Write skeleton equations
- For sodium oxide + water → sodium hydroxide:
- The skeleton equation is (Na_2O + H_2O\rightarrow NaOH).
- For iron (III) + hydrofluoric acid → hydrogen gas + iron (III) fluoride:
- The skeleton equation is (Fe+HF\rightarrow H_2 + FeF_3).
- For sulfuric acid + barium hydroxide → water + barium sulfate:
- The skeleton equation is (H_2SO_4 + Ba(OH)_2\rightarrow H_2O+BaSO_4).
- For (C_3H_8 + O_2\rightarrow CO_2 + H_2O), it is already in skeleton - form.
- For (BaCl_2+K_3PO_4\rightarrow KCl + Ba_3(PO_4)_2), it is already in skeleton - form.
Step2: Balance the equations
- For (Na_2O + H_2O\rightarrow NaOH):
- There are 2 sodium atoms on the left - hand side. So, we need 2 moles of (NaOH) on the right - hand side. The balanced equation is (Na_2O + H_2O = 2NaOH).
- For (Fe+HF\rightarrow H_2 + FeF_3):
- First, balance the fluorine atoms. We need 3 moles of (HF) to get 3 moles of (F) atoms. Then, to balance the hydrogen atoms, we need (\frac{3}{2}) moles of (H_2). Multiply through by 2 to get whole numbers. The balanced equation is (2Fe + 6HF=3H_2 + 2FeF_3).
- For (H_2SO_4 + Ba(OH)_2\rightarrow H_2O+BaSO_4):
- The number of (H), (S), (O) and (Ba) atoms on both sides is already equal when we consider the products and reactants directly. The balanced equation is (H_2SO_4 + Ba(OH)_2 = 2H_2O+BaSO_4).
- For (C_3H_8 + O_2\rightarrow CO_2 + H_2O):
- First, balance the carbon atoms. We need 3 moles of (CO_2) for 3 carbon atoms in (C_3H_8). Then, balance the hydrogen atoms. There are 8 hydrogen atoms in (C_3H_8), so we need 4 moles of (H_2O). Finally, balance the oxygen atoms. On the right - hand side, we have (3\times2 + 4\times1=10) oxygen atoms. So, we need 5 moles of (O_2) on the left - hand side. The balanced equation is (C_3H_8+5O_2 = 3CO_2 + 4H_2O).
- For (BaCl_2+K_3PO_4\rightarrow KCl + Ba_3(PO_4)_2):
- First, balance the barium atoms. We need 3 moles of (BaCl_2). Then, balance the potassium atoms. We need 6 moles of (KCl). The balanced equation is (3BaCl_2 + 2K_3PO_4=6KCl + Ba_3(PO_4)_2).
Answer:
- Skeleton: (Na_2O + H_2O\rightarrow NaOH); Balanced: (Na_2O + H_2O = 2NaOH)
- Skeleton: (Fe+HF\rightarrow H_2 + FeF_3); Balanced: (2Fe + 6HF=3H_2 + 2FeF_3)
- Skeleton: (H_2SO_4 + Ba(OH)_2\rightarrow H_2O+BaSO_4); Balanced: (H_2SO_4 + Ba(OH)_2 = 2H_2O+BaSO_4)
- Skeleton: (C_3H_8 + O_2\rightarrow CO_2 + H_2O); Balanced: (C_3H_8+5O_2 = 3CO_2 + 4H_2O)
- Skeleton: (BaCl_2+K_3PO_4\rightarrow KCl + Ba_3(PO_4)_2); Balanced: (3BaCl_2 + 2K_3PO_4=6KCl + Ba_3(PO_4)_2)