a) Zn(s) + 2HCl(aq) $\rightarrow$ ZnCl2(aq) + H2(g)
b) 2H2(g) + O2(g) $\rightarrow$ 2H2O(g)
johnmulu answered the question on April 6, 2017 at 08:38
- a) Explain what happens to the molecules of water in the region BC in terms of Kinetic theory.
b) In what state is the water in the region DE?
(Solved)
The graph below is a cooling curve for water. Study it and answer the questions that follow.
a) Explain what happens to the molecules of water in the region BC in terms of Kinetic theory.
b) In what state is the water in the region DE?
Date posted: April 6, 2017. Answers (1)
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Date posted: April 6, 2017. Answers (1)
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b) Which is the most soluble contaminant in P?
Date posted: April 6, 2017. Answers (1)
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Date posted: April 6, 2017. Answers (1)
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The graph below is a cooling curve of a substance from gaseous state to solid state.
Give the name of the: a) Process taking place between to and t1
b) energy change that occurs between between t3 and t4
Date posted: April 6, 2017. Answers (1)
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Sample of urine from three participants F, G and H at an international sports meeting were spotted onto a chromatography paper alongside two from illegal drugs A1 and A2. A chromatogram was run using methanol. The figure below shows the chromatogram.
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Date posted: April 6, 2017. Answers (1)
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a) What happens to the water molecules between points W and X?
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c) Explain why the temperature does not rise between points X and Y.
Date posted: April 6, 2017. Answers (1)
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Date posted: April 6, 2017. Answers (1)
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A piece of chromatography paper was spotted with coloured inks obtained from pens labeled 1 to 6. The diagram below show the spots after the chromatogram was developed.
a) Which two pens contained the same pigment?
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Date posted: April 5, 2017. Answers (1)
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The set-Up below represents the apparatus that may be used to separate a mixture of two miscible liquids C and D whose boiling points are 80oC and 110oC.
a) Name B
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c) Which liquid was collected in the test tube?
Date posted: April 5, 2017. Answers (1)
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Date posted: April 5, 2017. Answers (1)
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b) What method would the student use to test the purity of the distillates obtained?
Date posted: April 5, 2017. Answers (1)
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Which curve shows the variation in temperature for pure solid? Explain.
Date posted: April 5, 2017. Answers (1)
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b) What is meant by a radioactive substance
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Date posted: February 22, 2017. Answers (1)
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Date posted: February 22, 2017. Answers (1)
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Date posted: February 22, 2017. Answers (1)
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Date posted: February 22, 2017. Answers (1)
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The half-life of the isotope is 25 days(Solved)
M grammes of a radioactive isotope decayed to 5 grammes in 100 days
The half-life of the isotope is 25 days
a) What is meant by half-life?
b) Calculate the initial mass M of the radioactive isotope.
Date posted: February 22, 2017. Answers (1)
- An alkanol has the following composition by mass: Hydrogen 13.5%, oxygen 21.6% and carbon 64.9%
Determine the empirical formula of the alkanol (C = 12.0: H = 1.0; O = 16.0)(Solved)
An alkanol has the following composition by mass: Hydrogen 13.5%, oxygen 21.6% and carbon 64.9%
Determine the empirical formula of the alkanol (C = 12.0: H = 1.0; O = 16.0)
Date posted: February 22, 2017. Answers (1)
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a) Give the name of the first member of the alkene homologous series
b) Describe a chemical test that can be used to distinguish butanol from butanoic acid.
Date posted: February 22, 2017. Answers (1)