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One mole of Chlorine combines with certain weight of a metal giving 111g of its chloride. the same amount of metal can displace 2g of hydrogen from an acid. what is the atomic weight of the metal? |
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Answer» Answers : (1) let metal be x Cl2 + x = N* xCl ( n moles) 1 mole = 71g 111g 91 cl = 35.5g) see that as it replaces 2g H = replacing 2 moles of H or 2+ charge thus metal has 2+ charge as Ca, Mg etc or 2 moles of metal like Na, K etc..... as Cl ha 1- charge so its two moles are used in the metal CHLORIDE as: XCl2 type ( for Ca type metals ) or (but here it is this type - a quite logic) 2XCl type (for Na type) so weight of chloride = 111= 2* 35.5 + x so x=40 here see that Ca and K has this much MASS bt K has 1 charge so should hv used its two moles thus finally use weight would be 80g bt used is 40 g. so metal is Ca and its mass is 40 g |
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