Answer:- 9.98 grams.
Solution:- The given balanced equation is:
From this equation, there is 1:1 mol ratio between methanol and formic acid. We start with given grams of methanol and convert them to moles. Then using mol ratio the moles of foramic acid are calculated and finally converted to grams on multiplying by it's molar mass.
The calculations could easily be done using dimensional analysis as:
= 
Hence, 9.98 grams of formic acid can be formed from 6.95 grams of methanol.
Decomposition of a potassium superoxide happens according to the scheme:
4KO₂(s) + 2H₂O(l) → 4KOH(aq) + 3O₂(g)
m(K₂O)=4M(K₂O)m(O₂)/{3M(O₂)}
m(K₂O)=4×71.1×6.5/{3×32.0}≈19.3 g
Answer:
Chemistry has taught that ;
Unsaturated hydrocarbon molecules that contain one or more double bonds are called alkenes.
Alkynes are unsaturated hydrocarbons due to the fact that some of the carbons are connected to fewer than four neighbouring atoms.
Note : Alkenes contain at least one double bond, while alkynes contain at least one triple bond.
Explanation:
The formula of chalcopyrite is CuFeS₂.
The molar mass of chalcopyrite - 183.5 g/mol
The mass of Cu in 1 mol of chalcopyrite is - 63.5 g
When 183.5 g of chalcopyrite is mined, the mass of Cu obtained - 63.5 g
So if 63.g of Cu is needed mass of chalcopyrite required - 183.5 g
Then to gain 370 g of pure Cu - mass of chalcopyrite needed -183.5/63.5 x 370
therefore mass of chalcopyrite to be mined - 1069.21 g
