Compared to the energy of an electron in the second shell of an atom of sulfur the energy of the electron in

first shell is lower.

Explanation:

Compared to the energy of an electron in the second shell of an atom of sulfur the energy of the electron in the first shell is lower.

The greater the number of shell of the electron higher will be its energy state. So, electron in the second shell will have more energy than the electron in the first shell. However, the remove electron from the shell lower shell electrons will require more energy than the higher shell electron.

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