Chemistry, 10.08.2021 05:40 salvadorperez26
Pha loãng 60 ml dung dịch HNO3 có pH = 3 với nước thành 180 ml dung dịch mới có pH là bao nhiêu
Answers: 3
Chemistry, 22.06.2019 11:40
Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)
Answers: 1
Chemistry, 22.06.2019 11:40
Enzymes affect the reactions in living cells by changing the
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Chemistry, 22.06.2019 13:30
Which of the following natural processes is most likely to support the formation of an underwater sinkhole? a pollution buildup from deposited minerals b limestone cave collapsing due to changes in sea level c erosion of large amounts of sand moved by ocean waves d oxidation of rock formed by chemical weathering
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Chemistry, 23.06.2019 03:10
Which is true according to the law of conservation of energy
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Pha loãng 60 ml dung dịch HNO3 có pH = 3 với nước thành 180 ml dung dịch mới có pH là bao nhiêu...
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