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Chemistry

A Level

How can a student test for the prescence of a halide ion?

Add a drop of each liquid to individual test tubes.To each test tube, add dilute nitric acid and silver nitrate solution.A precipitate will form for each ion present.chloride= whitebromide= creamiodide= y...

Answered by Marco P. • Chemistry tutor

2562 Views

Describe the changes in equilibrium of ethanol production from ethene and water (enthalpy of reaction is ∆H = - 46 kJ/mol) when: (a) a high pressure is applied; (b) ethanol concentration is increased; (c) temperature is increased; (d) a catalyst is used.

The equation for the reaction (would be given for this type of question but I ran out of space): C₂H₄ (g) + H₂O (g) ⇌ C₂H₅OH (g) ∆H = - 46 kJ/molQues...

Answered by Aiste A. • Chemistry tutor

7947 Views

Using principles of structure and bonding, explain why sulfur has a higher melting point than phosphorus

Sulfur, which is naturally S₈has more electrons than Phosphorus, which is naturally P₄. Therefore the Van der Waals between molecules is stronger in Sulfur than it is in Phosphorus,...

Answered by Dalvin S. • Chemistry tutor

29482 Views

What is meant by the term 'Electronegativity'

Electronegativity, as denoted by the Greek letter 'chi', is the tendency of an atom to attract bonding electrons within a covalent bond. Let us unravel what this means. The term electronegativity may only...

Answered by Yeshurun T. • Chemistry tutor

3513 Views

Describe how you could distinguish between ethanol, ethanoic acid, ethyl bromide and 2-methylpropan-1-ol.

First, you should add sodium hydrogen carbonate to all three compounds. Ethanoic acid will react with this to release a gas which will turn limewater cloudy.
Second, you should add acidified potassi...

Answered by Emma W. • Chemistry tutor

5986 Views