Question

Ascorbic acid, of vitamin c (c6h8o6), is an essential vitamin. it cannot be stored by the body and must be present in the diet. what is the molar mass of ascorbic acid? vitamin c tablets are taken as a dietary supplement. if a typical tablet contains 500.0 mg of vitamin c, how many moles and how many molecules of vitamin c does it contain?

Answer 1

Answer:

Molar mass of ascorbic acid is 176 g.

The tablet contains 0.002841 moles and $1.711\times 10^{21}$ molecules of vitamin C.

Explanation:

Molar mass of vitamin C=$(6\times atomic mass of C)+(8\times atomic mass of H)+(6\times atomic mass of O)$ = $(6\times 12 g)+(8\times 1 g)+(6\times 16 g)$ = 176 g

We know, number of moles = $\frac{mass}{molar mass}$

So moles of vitamin C in 500.0 mg tablet = $\frac{0.5000 g}{176 g}$

                                                                     = 0.002841 moles

We know 1 mol of a compound contains $6.023\times 10^{23}$ molecules of that compound.

So number of molecules of vitamin C in 500.0 mg tablet = $0.002841\times 6.023\times 10^{23}$ molecules =  $1.711\times 10^{21}$ molecules

Answer 2

Molecular formula of ascorbic acid is $C_{6}H_{8}O_{6}$

Molar mass of ascorbic acid = $(6 * 12 g/mol) + (8 * 1 g/mol) + (6 * 16 g/mol) = 176 g/mol$

Converting 500.0 mg of ascorbic acid to moles: We use molar mass of ascorbic acid to convert mass to moles.

$500.0 mg * \frac{1 g}{1000 g} *\frac{1 mol}{176 g} = 0.00284 mol$

Converting 500.0 mg of ascorbic acid to molecules: The conversion factor used is 1 mole = $6.022*10^{23} molecules$

$500.0 mg * \frac{1 g}{1000 mg}*\frac{1 mol}{176 g} * \frac{6.022*10^{23}molecules}{1 mol} = 1.71 * 10^{21} molecules$