Anonymous
Anonymous asked in Science & MathematicsChemistry · 2 months ago

# Chem questions?

1.Normal saline solution contains 0.90 g of sodium chloride per 100. mL of solution. What is the molar concentration (M) of sodium chloride in normal saline?

2.How would you prepare 250. mL of 0.300 M LiNO3 solution, starting from the solid solute? Do a calculation AND write one sentence describing how you would prepare the solution.

Relevance
• 2 months ago

1.

(0.90 g NaCl) / (58.4430 g NaCl/mol) / (0.100 L) = 0.154 mol/L = 0.154 M NaCl

2.

(0.250 L) x (0.300 mol LiNO3/L) x (68.9459 g LiNO3/mol) = 5.17 g LiNO3

Supposing the solution to be made is aqueous:

Weigh out 5.17 grams of lithium nitrate, put it in a 250-mL volumetric flask, add enough water to dissolve the salt with swirling, add more water until the solution reaches the flask's mark, and mix thoroughly.

• 2 months ago

1)

.90 g  x. 1mol/ 58.44 g = .015 mol NaCl

.015 mol /.1L = .15M

2)

250 ml = 0.25 L of 0.300 M LiNO3

0.25 L x (.300 mol/L) = .075 moles  LiNO3

Amount of solid  LiNO3 required in grams

0.075 moles  LiNO3 x 68.946 g/mol LiNO3 = 5.17 g LiNO3