How many moles of calcium carbonate (CaCO3) are present in 10 g of the substance? (Ca = 40 u; C = 12 u; O = 16 u)

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How many moles of calcium carbonate (CaCO₃) are present in 10 g of the substance? (Ca = 40 u; C = 12 u; O = 16 u)

Molar mass of calcium carbonate (CaCO₃) = 40+12+48 = 100g

Mass of the substance = 10g

As we know that, Number of moles = mass of an element/molar mass of an element

Hence Number of moles = 10/100 = 0.1 mole.

Calculate the mass of 12.044 × 10²⁵ molecules of oxygen (O₂).

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