Answer:
Na2SO4 means: two moles sodium (45.98 g), one mole sulfur (32.06 g), and four moles oxygen (64.00 g) combine to form one mole of sodium sulfate (142.04 g).
Explanation:
Henry's law constant for oxygen is 0,0013 mol/L·<span>atm. Air has 21,0% oxygen.
concentration of oxygen at 1 atm: 0,0013 mol/L</span>·atm · 0,21 · 1 atm = 0,000273 mol/l.
concentration of oxygen at 1 atm: 0,0013 mol/L·atm · 0,21 · 0,892 atm = 0,000243 mol/l.
difference in concentration: 0,000273 - 0,000243 = 0,00003 mol/L.
n(oxygen) = 0,00003 mol/L · 4,40 L = 0,000132 mol.
Answer:
The weight-average molar mass of polystyrene is 134,160 g/mol.
Explanation:
Molar mass of the monomer styrene ,
, M=104 g/mol
Given , number average molar mass of the polymer , M'= 89,440 g/mol
Degree of polymerization = n

The weight-average molar mass = 
Molar mass dispersity is ratio of weight-average molar mass to the number average molar mass of the polymer.



The weight-average molar mass of polystyrene is 134,160 g/mol.