Heat change when one mole of a solute dissolves in excess of the solvent until there is no further change in temperature.
johnmulu answered the question on February 15, 2017 at 07:16
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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A compound whose general formula is M(OH)3 reacts as shown by the equation below.
M(OH)3(s) + OH$^-_4$(aq) $\rightarrow$ M(OH)$^-_4$(aq)
M(OH)3(s) + 3H+(aq) $\rightarrow$ M3+(aq) + 3H2O(l)
a) What name is given to compounds which behave like M(OH)3 in the two reactions
b) Name two elements whose hydroxides behave like that of M.
Date posted: February 15, 2017. Answers (1)
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When magnesium burns in air, it forms a white solid and a grey-green solid. When a few drops of water are added to the mixture, a gas that turns red litmus paper blue is evolved.
Identify the:
i) White solid
ii) Gas evolved and the gas
I) Name of gas
II) Use of the gas.
Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Date posted: February 15, 2017. Answers (1)
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Soap dissolves in water dissolves in water according to the equation below; NaSt(aq) $\rightarrow$ Na+(aq) + St- where St- is the stearate ion.
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Date posted: February 13, 2017. Answers (1)
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Date posted: February 13, 2017. Answers (1)
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Date posted: February 13, 2017. Answers (1)
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b) Name two chemicals that are used to remove hardness of water.
Date posted: February 13, 2017. Answers (1)
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The elements nitrogen, phosphorous and potassium are essential for plant growth.
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Describe how a sample of a fertilizer may be tested to find out if it contained nitrate ions.
Date posted: February 13, 2017. Answers (1)