Answer:
Molarity: 0.092M
Molality: 0.090m
Explanation:
Molarity, M, is defined as the moles of solute (In this case, C14H12 -Molar mass: 180.25g/mol-) in 1L of solution.
The molality, m, are moles of solute per kg of solvent.
<em>Molarity:</em>
<em>Moles solute: </em>
7.9g * (1mol/180.25g) = 0.04383 moles
<em>Liters solution:</em>
475mL = 0.475L
Molarity: 0.04383 moles / 0.475L = 0.092M
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<em>Molality:</em>
<em>kg solvent:</em>
475mL * (1.03g/mL) = 489.25g = 0.48925kg
Molality:
0.04383 moles / 0.48925kg = 0.090m