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# Number of moles of glucose molecules

## How many moles of glucose molecules are present in 1.8 grams of a
sample of glucose?

Logic:

The molar mass, sometimes referred to as molecular weight, is the mass of one
mole of a substance and is usually expressed in grams.

Therefore,

In general,

**Calculation of molar mass of glucose (C**_{6}H_{12}O_{6})

The molar mass of glucose can be calculated from the molar masses of
individual atoms present in it. From the molecular formula, C_{6}H_{12}O_{6},
one can find there are 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms in
one molecule of glucose.

Molar mass of C = 12 g mol^{-1}

Molar mass of H = 1 g mol^{-1}

Molar mass of O = 12 g mol^{-1}

There fore,

Molar mass of C_{6}H_{12}O_{6}=(6x12) +
(12x1) + (6x16) = 72 + 12 + 96 = 180 g mol^{-1}

**Answer:**

Now we can calculate the number of moles of glucose as follows:

Calculation of number of molecules

It is also possible to get the number of molecules in the given sample by
multiplying the number of moles with Avogadro number, N_{A}

Thus,

the number of molecules = n.N_{A}

Where N_{A} = 6.022 x 10^{23}

In above glucose sample,

the no. of glucose molecules = 0.01 x 6.022 x 10^{23} =
6.022 x 10^{21}

Remember that one mole of any substance contains Avogadro number of particles
(may be atoms or molecules or ions etc.). If the substance is molecular, the
number molecules will be equal to 6.022 x 10^{23}. If we take atomic
substance, then the number of atoms in one mole is equal to Avogadro number.

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Author: Aditya vardhan Vutturi