At times, water supplied by municipal council is treated with chemicals to destroy germs and impurities. What if the colour or odour of water changes?
As long as the colour and odour of the chemicals dominate the water, it is not fit for tahaarat.
Is the quantity of water to be used for wuzu or gusul fixed?
The quantity of water is not fixed, but, there is no sawaab in using excess water for performing wuzu or gusul. Excessive usage is wastage and is attributed to satanic instincts. Rasulullah (SAW) used to perform kaamil wuzu and gusul with minimum water.
A person wants to pray namaaz and the last time of namaaz has arrived. There are two vessels of water; one contains paak water, while the other has napaak water. Unfortunately, the person does not know which is which, what should he do?
If he does not know which vessel has paak water and which has napaak water, the person should do tayammum and pray namaaz.