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^(@)

The surface tension of water at 21°C is 72.75 xx 10^(3) Nm^(-1). A 33

1.	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^(@)
Answer» Solution :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.