Why do metals decrease in mass in acids?

1 Answer
Jul 15, 2017

Well masses are constant in chemical reactions.........

Explanation:

So I assume you are asking why you might get more mass out of a reaction between a metal and an acid with respect to the mass of the metal you put in.......

Metals tend to form salts in acids....... And for a simple reaction we could advance.......

#Mg(s) + 2HCl(aq) rarr MgCl_2(s)+H_2(g)uarr#

And thus were to use a #5*g# mass of metal, we would get an equimolar quantitiy of magnesium chloride........

And thus mass of #MgCl_2-=............#

#(5*g)/(24.3*g*mol^-1)xx95.2*g*mol^-1~=20*g# with respect to the salt............

What mass of dihydrogen gas would be evolved in this reaction? Why would it be easier to measure the volume of the gas evolved?