Question

how can you study experimentally that water is made of hydrogen amd oxygen in the ratio 2:1 by volume​

Answer 1

by electrolysis method mate

Answer 2

to known that water contain 2 parts of hydrogen and 1 part of oxygen

#take a bottle attach a rubber cork to it and put the bottle in inverted position

# take 2 test tube filled with water

# now take a 6 volt battery and attach through the wire to the 2carbon electrode

# now switch on the battery you will see that a bubbles of gas is evolved # now test with the help of burning candle # another test tube which burns brightly it is oxygen...hope it helps you..