two gram portion of impure sodium chloride was dissolved in water .excess of silver nitrate was added to ppt 4.628 grams of silver chloride
calculate the % of chlorine in the sample

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a three gram portion of impure barium chloride was dissolved in water .excess of sodium sulphate was added to ppt 2 gram of barium sulphate . calculate the % of barium in the sample
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co2 concentration in water 200 ppm or higher is lethal to fish . will river water that contain 0.62 g of dissolved co2 per 2 kg be toxic to fish
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2cuo+cu2>>>> 4cu +so2
calculate the mass of copper (I) sulphide ore , which contain 30%
impurities needed to produce 3 ton of copper metal