The molar standard enthalpy/heat of reaction may be defined as the energy/heat change when one mole of products is formed at standard conditions
A chemical reaction involves the reactants forming products. For the reaction to take place the bonds holding the reactants must be broken so that new bonds of the products are formed. i.e.
A-B + C-D -> A-C + B-D
The energy required to break one mole of a (covalent) bond is called bond dissociation energy.
The SI unit of bond dissociation energy is kJmole-1.
The higher the bond dissociation energy the stronger the (covalent)bond
Wilfykil answered the question on February 19, 2019 at 12:50
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Date posted:
February 19, 2019
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February 19, 2019
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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Fill a burette wuth 0.1M dilute sulphuric(VI)acid. Pipette 20.0cm3 of 0.1M sodium hydroxide solution into a 250cm3 conical flask. Add three drops of phenolphthalein indicator. Titrate the acid to get a permanent colour change.Repeat with 0.1M potassium hydroxide solution in place of 0.1M sodium hydroxide solution.
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Date posted:
February 19, 2019
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Place 5cm3 of 0.2M dilute sulphuric(VI)acid into four separate clean boiling tubes. Add about 0.1g of copper(II)oxide to one boiling tube. Stir.
Repeat by adding Zinc oxide, calcium carbonate and Sodium (II)Oxide in place of the Copper(II)Oxide
State and explain the observations made.
Date posted:
February 19, 2019
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Answers (1)
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(Solved)
Put about 2cm3 of Concentrated sulphuric (VI) acid into two separate boiling tubes. Place a thin moist/damp/wet filter paper dipped in acidified potassium dichromate (VI)solution on the mouth of the boiling tube.
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Date posted:
February 19, 2019
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Answers (1)
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Put about 2 cm3 of Concentrated sulphuric (VI) acid into three separate boiling tubes. Place a thin moist/damp/wet filter paper dipped in acidified potassium dichromate (VI)solution...
(Solved)
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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Answers (1)
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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(Solved)
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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Date posted:
February 19, 2019
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February 19, 2019
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Date posted:
February 19, 2019
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February 19, 2019
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February 19, 2019
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