Page 160 - Chemistry ICSE Class X
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146                                                                                     ICSE Chemistry – 10

            — Composition of a compound. The mass percentage of each element present in a compound is termed as its composition.
            — Molecular formula. A shorthand notation for the molecule of a substance in terms of symbols, and numbers of atoms of
                each element present in it, is called its molecular formula.
                Covalent compounds which exist as discrete molecules can be described by their molecular formulae.

                Ionic and giant network covalent compounds are described by their empirical or stoichiometric formulae.
            — Empirical formula. The simplest formula which gives the lowest whole-number ratio between the number of atoms of
                different elements present in the substance is called as empirical formula.
                Molecular formula of a substance = n × Empirical formula of the substance


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