Preparation And Properties Of Acids
Preparation of acids:
1. From Non metals.
Elements such as carbon, sulphur, phosphorous etc. are burnt in oxygen and form their oxides.These Oxides when dissolved in water forms respective acids, and hence such non metallic oxides are called acidic oxides.
a) C + O2 \(\to\) CO2
Carbon + Oxygen \(\to\) Carbon dioxide
b) \(C{O_2} + {H_2}O\xrightarrow{{}}{H_2}C{O_3}\)
Carbon dioxide + water \(\to\) Carbonic acid
c) S + O2 \(\to\) SO2
Sulphur + Oxygen \(\to\) Sulphur dioxide
d) \(S{O_2} + {H_2}O\xrightarrow{{}}{H_2}S{O_3}\)
Sulphur dioxide + water \(\to\)Sulphurous acid
e) \(S{O_3} + {H_2}O\xrightarrow{{}}{H_2}S{O_4}\)
Sulphur trioxide + water \(\to\) Sulphuric acid
f) \({N_2}{O_5} + {H_2}O\xrightarrow{{}}2HN{O_3}\)
Nitrogen pentoxide + water \(\to\) Nitric acid
g) \({P_2}{O_5} + 3{H_2}O\xrightarrow{{}}2{H_3}P{O_4}\)
Phosphorous pentoxide + water \(\to\) Phosphoric acid
h) \({P_2}{O_3} + 3{H_2}O\xrightarrow{{}}2{H_3}P{O_3}\)
Phosphorous trioxide + water \(\to\) Phosphorous acid
i)\({N_2}{O_3} + {H_2}O\xrightarrow{{}}2HN{O_2}\)
Dinitrogen trioxide +water\(\to\) Nitrous acid
2. By direct combination of Elements.
\({H_2} + C{l_2}\xrightarrow{{sunlight}}2HCl\)
\({H_2} + S\xrightarrow{{boiling}}{H_2}S\)
Volatile acids:
The acids, which easily changes into their vapours, either at room temperature or heating below 1000C, are called volatile acids.
Ex: HCl, HNO3, H2SO3 and H2CO3
Non-volatile acids:
The acids, which do not change into their vapours, even on strong heating are called non-volatile acids. Ex: H2SO4