Molecular mass for Manganese is 54.938049
so
100%=54.938049×100/.388=14159.290979381
N, our atmosphere is about 80% nitrogen(N) and about 20% oxygen(O)
Answer: 0.67 ml
Explanation:
According to the dilution law,
where,
= concentration of stock solution = 226 mg/ml
= volume of stock solution = ?
= concentration of working solution= 15 mg/ml
= volume of working solution= 10 ml
Putting in the values we get:

Thus volume of stock solution needed to dilute to have 10mL of working solution at the above concentration is 0.67 ml
The % yield if 500 g of sulfur trioxide reacted with excess water to produce 575 g of sulfuric acid is calculated using the below formula
% yield = actual yield/ theoretical yield x100
actual yield =575 grams
to calculate theoretical yield
find the moles of SO3 used =mass/molar mass
= 500g/ 80 g/mol =6.25 moles
SO3+H2O=H2SO4
by use of mole ratio of SO3 : H2SO4 which is 1:1 the moles of H2SO4 is also= 6.25 moles
the theoretical yield of H2SO4 is therefore = moles /molar mass
= 6.25 x98= 612.5 grams
%yield is therefore= 575 g/612 g x100= 93.9 %