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Chemistry

A Level

What are the reagents used to oxidise an alcohol to a carboxylic acid.

Answer: Sulphuric acid and potassium dichromate.

Answered by John A. • Chemistry tutor

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What is the pH of a 25 ml sample of 0.2 M sulfuric acid? What is the pH after 5 ml of 0.25 M sodium hydroxide is added?

H₂SO₄ fully dissociates into ions (strong acid). It is diprotic therefore concentration of H⁺ ions is twice that of the acid = 0.4 M. pH = -log[H⁺] = -log[0.4] ...

Answered by George R. • Chemistry tutor

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Explain why the boiling point of PH3 is lower than the boiling point of AsH3

AsH3 is a larger molecule than PH₃ as As is lower down the periodic table, so has a higher atomic number so more electrons. Therefore AsH₃ has more electrons than PH₃ mean...

Answered by Freya O. • Chemistry tutor

24695 Views

Explain why Carbon Dioxide has a linear shape with a bond angle of 180 degrees

Carbon Dioxide consists of 1 carbon atom covalently bonded to two oxygen atoms.Carbon is in group 4 and so has 4 electrons in its outer shell.Carbon shares two pairs of electrons with each of the oxygen a...

Answered by Richard P. • Chemistry tutor

17016 Views

What chemical test can be used to differentiate between alkenes and alkanes. Describe and explain the results.

Alkenes decolourise bromine water (orange/brown to colourless) while alkanes cause no change in colour. An electrophilic addition reaction occurs with the alkene. In a reaction between et...

Answered by Sito E. • Chemistry tutor

11234 Views