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chemistry helppp

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1) PET is a polymer most commonly known for it's use in soft drink bottles. It is synthesised by condensing the two molecules seen in the figure below. If 4,340 g of ethylene glycol and 11,620 g terephthalic acid are reacted completely to generate PET, how many grams of H2O are generated?(Use the following... 顯示更多 1) PET is a polymer most commonly known for it's use in soft drink bottles. It is synthesised by condensing the two molecules seen in the figure below. If 4,340 g of ethylene glycol and 11,620 g terephthalic acid are reacted completely to generate PET, how many grams of H2O are generated? (Use the following atomic masses in your calculations: C = 12, H = 1, O = 16. You final answer should be a whole number.) 2) The two monomeric units seen in the figure below may polymerise to form a polymer known as KevlarTM, and hydrogen chloride gas. KevlarTM is trademarked the chemical company DuPont, who claim that it is "...5 times stronger than steel on an equal weight basis...". This is attributed to the strong intermolecular bonds between adjacent chains of the polymer. In an industrial production of KevlarTM, equal molar amounts of 1,4-phenylene-diamine and terephthaloyl chloride are reacted completely to generate 6,570 g of hydrogen chloride gas. How many grams of 1,4-phenylene-diamine were used in the synthesis? thank you so much!!

最佳解答:

1. both reactants are bi-functional, meaning that 1 mole of each reactant reacts to give 2 mole of water: nCH2OH-CH2OH + nC6H4-(COOH)2 ----------> -[-CH2CH2-OCOC6H4COO-]n- + 2H2O Check for excess / limiting reagent: molar mass of ethylene glycol = 62 g/mol no. of mole = mass / molar mass = 4340 / 62 = 70 mole molar mass of terephthalic acid = 166 g/mol no. of mole = 11620 / 166 = 70 mole thus they react completely. no. of mole of water = 140 mole mass = no. of mole x molar mass = 140 x 18 = 2520 g. 2. 1,4-phenylenediamine: C6H4(NH2)2 terephthaloyl chloride: C6H4(COCl)2 nC6H4(NH2)2 + nC6H4(COCl)2 ---------> -[-NH-C6H4-NH-CO-C6H4-CO-]n- + 2HCl both reactants are bi-functional, meaning that 1 mole of each reactant reacts to give 2 mole of hydrogen chloride: no. of mole of HCl = mass / molar mass = 6570 / 36.5 = 180 mole no. of mole of each reactant = 180/2 = 90 mole molar mass of 1,4-phenylenediamine = (12x6 + 1x4 + 14x2 + 1x4) = 108 g/mole mass = no. of mole x molar mass = 90 x 108 = 9720 g