Question

Within 2 hours after eating, a normal blood glucose (C6H12O6, 180.2 g/mol) level will be below 140 mg/dL (that is, 140 mg/100 mL). What is this concentration in molarity (mol/L)? Please show work!

Answer 1

level = 140 mg/100 mL

Consider 1 L of solution that is 1000 mL

Since level is 140 mg/100 mL

Then, mass of glucose = 1400 mg since = 1.4 g

Lets convert this to number of mol.

Molar mass of C6H12O6,

MM = 6*MM(C) + 12*MM(H) + 6*MM(O)

= 6*12 + 12*1 + 6*16

= 180 g/mol

mass(C6H12O6)= 1.4 g

number of mol of C6H12O6,

n = mass/molar mass

=(1.4 g)/(180 g/mol)

= 0.00778 mol

volume , V = 1 L

Molarity,

M = number of mol / volume in L

= 0.00778 mol /1 L

= 0.00778 mol/L

Answer: 0.00778 mol/L