Question

Write the balance chemical equations for the following
1. Hydrogen combines with oxygen to form water
2. Nitrogen reacts with hydrogen to produce ammonia
3. Sodium bicarbonate decomposed into sodium carbonate, water and carbon dioxide.
4. Aluminium combines with oxygen to give aluminium oxide
5. Magnesium reacts with hydrochloric acid to form magnesium chloride and hydrogen.

Answer 1

1. When molecular hydrogen (H2) and oxygen (O2) are combined and allowed to react together, energy is released and the molecules of hydrogen and oxygen can combine to form either water or hydrogen peroxid
2. The following chemical reaction takes place when hydrogen gas interacts with nitrogen to form ammonia. Hydrogen and nitrogen react together to form ammonia in this scenario.
3. Sodium hydrogen carbonate (also known as sodium bicarbonate or bicarbonate of soda) has the chemical formula NaHCO3. When it is heated above about 80°C it begins to break down, forming sodium carbonate, water and carbon dioxide. This type of reaction is called a thermal decomposition.
4. 4 moles of Al reacts with 3 moles of O2 to get 2 Moles of aluminium oxide. 0.5 moles of Al reacts with 0.5x 3/4 = 0.375 moles of oxygen.
5. Magnesium reacts with hydrochloric acid according to the equation: Mg(s) + 2 HCl(aq) --> MgCl 2(aq) + H 2(g) This demonstration can be used to illustrate the characteristic reaction of metals with acid, a single replacement reaction, or to demonstrate the generation of hydrogen gas.

Answer 2

$\bf\huge{Answer :}$

1. Hydrogen combines with oxygen to form water.

• $\bf{2H_2\:(g) +O_2\longrightarrow2H_2O\:(l) }$

2. Nitrogen reacts with hydrogen to produce ammonia.

• $\bf{3H_2 + N_2\longrightarrow\:2NH_3}$

3. Sodium bicarbonate decomposed into sodium carbonate, water and carbon dioxide.

• $\bf{2NaHCO_3\longrightarrow\:Na_2CO_3+H_2O+CO_2}$

4. Aluminium combines with oxygen to give aluminium oxide.

• $\bf{4Al+3O_2\longrightarrow\:2Al_2O_3}$

5. Magnesium reacts with hydrochloric acid to form magnesium chloride and hydrogen.

• $\bf{Mg+2HCl\longrightarrow\:MgCl_2+H_2}$

$\bf\huge{ Additional \:Information :}$

Balanced Chemical equation: A balanced chemical equation is that in which the total number of atoms of each element is equal on both side of the equation.

• The balanced chemical equation is based on the "law of conservation of mass".

The chemical equation can be made more informative by applying symbols :

• Solid - (s)
• Liquid - (l)
• Gases - (g)
• Aqueous solution - (aq)
• Reactants which produce gas in reaction - (↑)
• Reactants which produce solid in reaction - (↓)

The techniques for balancing a chemical equations are :

• Hit and trial method
• Algebraic method (easiest method according to me.)
• Partial equations method.
• Oxidation number method.
• Ion-electron method.