Excess concentrated sulphuric VI acid was mixed with pieces of dry wood as shown.

Excess concentrated sulphuric VI acid was mixed with pieces of dry wood as shown.

a) State the observation made in the tube.

b) When the reaction was complete, the mixture was heated gently, then strongly and set up adjusted as shown below.

State and explain the observation made on acidified potassium chromate VI solution.

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a) - Dry wood changes to black
- bubbles of colourless gas

b) Acidified K₂Cr₂0₇ changes from orange to green

Conc. H₂S0₄ reduced to S0₂ which reduce acidified to
chromium ions (Cr³⁺) which are green in colour

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maurice.mutuku answered the question on September 18, 2019 at 08:47

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