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`100 g` sample of clay (containing 19% `H_(2)O`, 40% silica, and inert inpurities as rest) is partically dried so as to contains 10% `H_(2) O`. Which of the following `is//are` correct statements (s) ?A. The percentage of silica in it is 44.4%B. The mas of partically dried clay is `90.0 g`.C. The precentage of inert impurity in it is 45.6%D. The mass of water evaporated is `10.0 g` |
Answer» Correct Answer - A::C `underset({:(%"in original clay"implies),(%"after partial drying"implies):})( ) underset({:(40),(a):})("Silica") underset({:(19),(10):})(H_(2)O) underset({:(100 - (40 + 19) = 41),(100 - (a + 10) = 90 - a):})("Impurities)` On heating, only water evaporates from clay, whereas silica and impurities are left as it is. Therefore, % ratio of silica and impurities remains unchanged, i.e., `(40)/(a) = (41)/(90 - a), :. a = 44.4%` % of mipurities after partial drying `= (19 - 10) = 9 g` `= 45.6%` Mass of `H_(2) O` evaporated `= (19 - 10) = 9 g` |
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