Question

a 0.150 m sodium chloride solution is referred to as a physiological saline solution because it has the same concentration of salts as normal human blood. calculate the mass of solute needed to prepare 275.0 ml of a physiological saline solution. multiple answer 1 point 41.3 g 8.77 g 16.1 g 31.9 g 2.41 g

Explanation:

Step1: Convert volume to liters

$V = 275.0\ mL=275.0\times10^{- 3}\ L$

Step2: Use the molarity formula $n = M\times V$

$n = 0.150\ mol/L\times275.0\times10^{-3}\ L=0.04125\ mol$

Step3: Find the molar - mass of $NaCl$

The molar - mass of $NaCl$, $M_{NaCl}=22.99\ g/mol + 35.45\ g/mol=58.44\ g/mol$

Step4: Calculate the mass of $NaCl$

$m=n\times M_{NaCl}=0.04125\ mol\times58.44\ g/mol\approx2.41\ g$

Answer:

2.41 g