2HgO=2Hg + O2
433,18 g. = 32 g
x. = 250 g
x= 3 384,21875 g of HgO is needed
And a water molecule, this is called a dehydration synthesis. when 2 molecule combine, a water molecule leave.
Answer:

Explanation:
Formula for the calculation of no. of Mol is as follows:

Molecular mass of Ag = 107.87 g/mol
Amount of Ag = 5.723 g

Molecular mass of S = 32 g/mol
Amount of S = 0.852 g

Molecular mass of O = 16 g/mol
Amount of O = 1.695 g

In order to get integer value, divide mol by smallest no.
Therefore, divide by 0.02657



Therefore, empirical formula of the compound = 
Answer:
The answer is Sodium Sulfate = Na2SO4
Explanation:
Molar mass of sulfate = 1 (S) + 4 (O) = 1 (32) + 4 (16) = 32 + 64 = 96
Molar mass of sodium sulfate = 2 (23) + 96 = 46 + 96 = 142
% of Sulfate = (96/142)*100 = 67.6%
Percent mistake in Studen A,
(I) % mistake = (67.6 - 68.6)/67.6 = 1.48
(ii) % mistake = (67.6 - 66.2)/67.6 = 2.07
(iii) % mistake = (67.6 - 67.1)/67.6 = 0.74
For understudy B
(I) % mistake = (67.6 - 66.7)/67.6 = 1.33
(ii) % mistake = (67.6 - 66.6)/67.6 = 1.48
(iii) % mistake = (67.6 - 66.5)/67.6 = 1.63
Sutdent An is some how exact.
Understudy B is exact however not precise.