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JEE MainChemistrySome Basic Concepts of Chemistry

An organic compound contains Carbon, Hydrogen, and Oxygen. The mass of Carbon in the compound is 9 times the mass of Hydrogen, and the mass of Oxygen is 4 3 times the mass of Carbon. If the molar mass of the compound is 176 g mol ⁻¹ , the number of hydrogen atoms present in one molecule of the compound is _______.

Correct answer

8

Step-by-step solution

Let the mass of Hydrogen in the compound be x . Then, the mass of Carbon is 9x . The mass of Oxygen is 4 3 9x = 12x . The mass ratio of C : H : O is 9x : x : 12x = 9 : 1 : 12 . To find the mole ratio, we divide the mass ratio by the respective atomic masses: Moles of C = 9 12 = 0.75 Moles of H = 1 1 = 1 Moles of O = 12 16 = 0.75 The simplest whole number ratio is obtained by dividing by 0.75 and multiplying by 3 (or simply multiplying the ratios by 4 ): C : H : O = 3 : 4 : 3 The empirical formula of the compound is

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