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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