By nonmetals, metals, and gases
Answer:
[HOCH₂CH₂OH] = 24.1 m
Explanation:
Ethylene glycol → HOCH₂CH₂OH
60% by mass means that 60 g of ethylene glycol are contained in 100 g of solution.
Solution mass = Solute mass + Solvent mass
100 g = 60 g + Solvent mass
Solvent mass = 40 g
Molality are the moles of solute contained in 1kg of solvent.
We determine the moles of solute → 60 g . 1mol/62 g = 0.967 moles
We convert the mass of solvent from g to kg → 40 g . 1kg/1000 g = 0.04 kg
Molality → 0.967 mol / 0.04 kg = 24.1 m
Answer:
Mass of oxygen = 2.2 g
Explanation:
Given data:
Mass of benzoic acid= 8.20 g
Mass of oxygen= ?
Solution:
Molar mass of oxygen = 16×2 g/mol
Molar mass of C₆H₅COOH = 7×12 + 1×6 + 2×16
Molar mass of C₆H₅COOH = 84 + 6 + 32
Molar mass of C₆H₅COOH = 122g/mol
Mass of oxygen in 8.20 g of C₆H₅COOH :
Mass of oxygen = 32 g.mol⁻¹/122 g.mol⁻¹ × 8.20 g
Mass of oxygen = 2.2g
