Concentrations

A solution contains 2000 mg of glucose in 500 mL of solution. What is the concentration in mg/mL?

• 4 mg/mL
• 5 mg/mL
• 10 mg/mL
• 2 mg/mL

The concentration of a solution is 4 mg/mL. What is this concentration in g/L?

• 5 g/L
• 0.4 g/L
• 40 g/L
• 4 g/L

A solution has 5 g of salt in 200 mL of water. What is the percentage concentration (w/v)?

• 5.0%
• 2.5%
• 1.0%
• 10.0%

50 mL of ethanol is mixed into 450 mL of water. What is the percentage concentration (v/v)?

• 20%
• 15%
• 10%
• 5%

A sample contains 0.003 g of a compound in 2 L of water. What is the concentration in ppm?

• 1500 ppm
• 1,5 ppm

• 15 ppm

• 0,15 ppm

How many grams of solute are needed to prepare 1 L of a 5% (w/v) solution?

• 75 grams
• 50 grams
• 100 grams
• 25 grams

Calculate the molarity if 29 g of NaCl (M = 58.5 g/mol) is dissolved in 500 mL of solution.

• 0.500 M
• 0.750 M
• 0.992 M
• 1.200 M

How many grams of CaCl₂ are needed to make 250 mL of a 0.4 M solution? (Molar mass = 111 g/mol)

• 20.0 g
• 5.5 g
• 15.0 g
• 11.1 g

How much water should be added to 100 mL of a 2 M solution to make it 0.5 M?

• 400 mL
• 300 mL
• 200 mL
• 100 mL

If a solution has a concentration of 10 mg/L, what is its concentration in ppm?

• 5 ppm
• 10 ppm
• 15 mg/L
• 100 ppm