Calculate the number of atoms of carbon present in 25 g of caco3 ?

1.506 × 10²³ carbon atoms

Explanation:

First we calculate the number of moles of calcium carbonate (CaCO₃) contained in 25 g.

number of moles = mass / molecular weight

number of moles of CaCO₃ = 25 / 100 = 0.25 moles

Now we make use of Avogadro's number which tell us that we have 6.022 × 10²³ molecules (or atoms) in one mole of substance.

Now in our case:

if in         1 mole of CaCO₃ we have 1 × 6.022 × 10²³ carbon atoms

then in   0.25 moles  of CaCO₃ we have X carbon atoms

X = (0.25 × 1 × 6.022 × 10²³) / 1

X = 1.506 × 10²³ carbon atoms

Learn more:

Avogadro's number

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