Answer:
Concept of Percent
Explanation:
1st => Try to understand the definition of percent (%)
Percent (% ) = (Part/Total) x 100%
Part => represents the item of interest ( in this case mass of evap dish) = 37.593g
Total => represents the combined total of all items in a mix ( evap dish + SiO₂) = 38.072g
∴Wt % of evap dish = part/total x 100% = 37.593g/38.072g x 100% = 98.726%
Now, if you wish to have the %SiO, the same idea applies. That is,
%SiO₂ = (Wt of SiO₂ / Wt of Evap Dish + SiO₂) x 100%
= (0.4805g/28.072g) x 100% = 1.274% SiO₂
To check work, add %Evap Dish + %SiO₂ = 98.726% + 1.274% = 100%
NOTE => Percent(%) is always a fraction (Part) of some total combined mix of items (Total).
Best of Luck, Doc :-)
