Question

"A 2.00 L graduated cylinder contains 1.40 L of buffer solution. The density of the buffer solution is 1.02 g/mL. What is the mass in grams of the buffer in the cylinder

Answer 1

Answer:

• 1,430 g

Explanation:

1) Data:

a) V = 1.40 liter

b) D = 1.02 g/ml

c) M = ?

2) Chemical principles and formula:

Density is a physical property which expresses the mass of matter contained per unit of volume.

In mathematical form it is given by the formula:

• density = mass / volume

• D = M / V

3) Calculations:

a) Convert liters to mililiters (ml):

• 1.40 liter × 1,000 ml / liter = 1,400 ml

b) Solve for M in the formula, substitute the data, and compute:

• D = M / V ⇒ M = D × V

• M = 1.02 g/ml × 1,400 ml = 1428 g ≈ 1430 g

Note that since the two data have 3 significant figures and the operation used is multiplication, the answer also has 3 significant figures.