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Which is heavier wet or dry cement?

Is cement heavier when it's wet or when it's dry?
Say, i have enough cement to make one cement block, would it be heavier when it's wet or when it dries into the block. Or would it weigh the same amount?
(just wondering, sorry if the question seems kind of dumb)


Wet, dumb@ss.

Wet is heavier, but no by very much. Dry concrete mix is Tricalcium silicate, Dicalcium silicate, Tricalcium aluminate, and Tetracalcium aluminoferrite. When water is added about 80% of the water contributes a reaction results which produces solids, Calcium silicate hydrate and Calcium hydroxide, and 20% evaporates.

Cement mostly is made on 1,2,3 formula ,which one unite is water .Mass of the other component will remain the same .Water during cure process will vaporized and cement will lose original weight by gram in each kilo .some water municols will be trapped in the cement in temperature under the 212 degree fahrenheit(100 celsius).The real weight of the cement (concrete) is calculated after curing (approx 2-3 week) .Which mean wet concrete has heavy germ than dry concrete .


if you have an empty cup and you put water in it............
if you have an gas can and you fill it with gas...............
ummm anytime you add mass to another mass it's mass increases... how could adding water to anything not increase its weight???

Yes wet is heavier... in a nutshell. I suspect that you are not referring to concrete vs. cement?

Concrete is mixed from cement. Cement as discussed earlier a mixture of minerals and silicate. When required to apply, water and other aggregates might be added to give it the tensile strength to do its job. Different mixture yields various strength variances and features.


I can answer this question because I JUST had to move two bags of cement. One bag was dry and although it was heavy, I was able to move it without a problem. The other bag somehow got wet. I could barely budge it and am waiting for my son to come and wrestle with the damn thing. It weighs a ton!!!

I am assuming you are referring to the weight of a quantity of cement mixed with the requisite water for molding (and not hardened) vs that same cement once it is in a fully cured (hardened) condition.

When cement hardens (cures) it does not lose all the water which was originally mixed with it, some of the water remains permanently incorporated into the cement. This is because the active ingredient in dry (as purchased) cement is primarily anhydrous calcium silicate*. When the cement cures and "dries out" it is in the form of a hydrate of calcium silicate and this portion of the water stays in the cement forever. When we mix cement with enough water so it can be poured or molded, we are adding more than the exact amount of water necessary for the hydration process, so, some, but not all, the water evaporates and thus, the wet cement would be heavier than hardened cement.

*Yes, there is sand, gravel, etc but these are just fillers, they just go along for the ride, they do not under go any chemical change during the process.