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HelloCthulhu
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Homework Statement
What is the molality of 1M NH4OH dissolved in 70.092ml of water? What is the total mass of the solution? What is the total volume? What is the concentration percent? What is the molar concentration?
1M NH4OH = 35.046g
density of water = 1g/ml
density of NH4OH = 0.88 g/ml
Homework Equations
molality = moles of solute/kg of solvent
mass = volume x density
molarity = moles of solute / liters of solution
concentration = moles / volume
The Attempt at a Solution
Solve for molality:
convert volume (ml) to mass (kg)
70.092ml x 1g/ml =70.092g / 1000 = 0.07092kg
1 / 0.070092 = 14.3 molals/kg
Solve for total mass:
35.046g + 70.092g = 105.138g
Solve for total volume:
convert mass(g) to volume(ml)
35.046g / 0.88g/ml = 39.825ml
39.825ml + 70.092ml = 109.917ml
Solve for concentration percent:
35.046g / 109.917ml=0.3188 x 100 = 31.88406= 32%Solve for molar concentration:
1M / 0.109917L = 9.09777M/L = 9.1M/L