How many atoms are in 17.3 mol Hg?

1.04x10^25 atoms

Explanation:

1 mole of any substance contains 6.02x10^23 atoms by Avogadro's hypothesis. This means that 1mole of Hg will also contain 6.02x10^23 atoms

If 1 mole of Hg = 6.02x10^23 atoms

Therefore, 17.3moles of Hg = 17.3x6.02x10^23 = 1.04x10^25 atoms

what is the question here. i think you messed up.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2