1] There is no special treatment while taxing capital gain income of of an senior citizen. except of getting higher slab of initial exemption as provided by Finance Act 2013 Ie Income up to Rs 2.5 lac is exempted in place of Rs 2 lacs.
2] If funds in the investment has come from yourself alone and name of mother is added only as joint owner then entire capital gain will be taxed in your hand and if your mother has contributed her share of investment then it will be taxed to the extent of her investment. If you have taken loan for purpose of purchase of said property and while computing taxable income in your case, you have claimed as deduction interest paid on loan then property is purchase in your name as per income tax record . If Property is given on rent then if you have included entire rent income in your hand then also capital gain will be taxed in your hand only.
The total capital Gain will be computed as under
Indexed value of investment 5,30,000*852/426 =Rs 10,60,000/-
Sale Value Rs 31,00,000/-
Less cost Rs 10,60,000/-
Taxable income Rs 20. 80 lacs. If you purchase a new house and entire capital gain ie Rs 20.80 lacs is invested then there will not be any tax as income is exempted us 54 of I T Act
In case your mother is 50% owner a so Incme taxble in her hands will be 10.40 llacs and has to pay tax accordingly.
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