The surface tension of water at 21°C is `72.75 xx 10^(3) Nm^(-1)`. A 33.24% (vol./vol.) solution of ethanol has `y = 33.24 xx 10^(-3) Nm^(-1)` at the same temperature. Given density (solution) = `0.9614 xx 10^3 kg m^(-3)` and density (water) = `0.9982 xx 10^3 kg m^(-3)`. How much less will the alcohol solution rise in the same capillary? Angle of contact, `theta = 0^(@)`

Explanation

We have,
`gamma = (hdrg)/2`
As the same capillary is used for both ethanol and water, r and g are the same in both.
`therefore h_(1)/h_(2) = (gamma_(1).d_(2))/(gamma_(2).d_(1))`
.1. and .2. stand for ethanol and water respectively.
`h_(1)/h_(2) = ((33.24 xx 10^(-3)) xx 0.9982 xx 10^(3))/((72.75 xx 10^(-3)) xx 0.9614 xx 10^(3)) = 0.474`
Thus, ethanol will rise only 47.4% as far as pure water.