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Question
Determine the empirical formula of a compound containing 47.9‰ K, 5.5‰ beryllium and 46.6‰ fluorine by mass.
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Solution
Determination of empirical formula :
| Element | Atomic mass | Percentage | Relative Number of moles | Simplest mole ratio | Whole number ratio |
| K | 39 | 47.9 | 47.9/39 =1.2 | 1.2/0.6 = 2 | 2 |
| Be | 9 | 5.5 | 5.5/9 = 0.6 | 0.6/0.6 = 1 | 1 |
| F | 19 | 46.6 | 46.6/19 =2.4 | 2.4/0.6 =4 | 4 |
The empirical formula of compound = K2BeF4.
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