Answer:
Theoretical yield of hydrogen is 1.11 g
Explanation:
Balanced equation, 
As Mg remain present in excess therefore HCl is the limiting reagent.
According to balanced equation, 2 moles of HCl produce 1 mol of
.
Molar mass of HCl = 36.46 g/mol
So, 40.0 g of HCl =
of HCl = 1.10 moles of HCl
Hence, theoretically, number of moles of
are produced from 1.10 moles of HCl = 
Molar mass of
= 2.016 g/mol
So, theoretical yield of
= 
When waves act together, you talk about "interference".
When they reinforce each other, it is "constructive interference".
When they cancel each other, it is "destructive interference".
IT will be easy to know how chemical reactions occur
It will helps to know the fundamental particles of an atom
Hello the term for weight is newton
hope this helped.
Cody