er is said to be a physical change while the latter process is said to be a chemical change.
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2. Calculate mass percentage of each element in the following compounds:
H2O, CaCl2, Al2O3, SiO2, CaCO3, NaHCO3, BaSO4, HCl, NaCl, KOH, HNO3, H2SO4, LiF, MgBr2, CO2, FeI2
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An organic compound has a density by hydrogen 43,5. Combustion of 17,4 grams of this compound gives 44 grams of carbon dioxide, 2,24 liters of nitrogen gas and 23,4 grams of water. What is the molecular formula of compound?
32
Write reactions according to the following schemes:
a) Methane -- Methyl bromide-- Ammonium methyl bromide -- Methyl amine -- Dimethyl amine
b) Carbon -- Aluminum carbide -- Methane -- Acetylene -- Benzene -- Nitrobenzene -- Aniline -- 2,4,6-tribromoaniline
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Write the molecular equations of three possible reactions between the following compounds: FeCl2, K2S, H2SO4, Ag, Cu(NO3)2 . Write the type of each reaction. For double displacement reaction write ionic equations.
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