Main Question or Discussion Point
Why the mercury in glass-laboratory thermometer doesn't stick to glass?
I'm not agree whit your opinion. Water is polar and it doesn't andhere to glass.Viscosity more has to do with how much the molecules of a liquid "stick" to each other and not to another substance like glass. Mercury doesn't adhere to glass well because it's nonpolar while glass is polar.
There are two reasons : first mecury has very high surface tension, i can't remember but probably about 4 or 5 times higher than that of water. It is so strong that any adhesion force can not compete with. According to my experience, Hg does not stick to any material except for the case it react to become an amalgam. Secondly, water is polar and so is glass. If water does not stick to glass, probably be the glass surface is not clean.Why the mercury in glass-laboratory thermometer doesn't stick to glass?
When you pour water out of a glass container, does all the water flow out? Nope, some stays stuck against the walls of the container!Water is polar and it doesn't andhere to glass.