Page 378 - SUBSEC October 2017_Neat

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(b) 20 cm of a solution of phosphorous (V) acid containing 1.96 g dm reacted with 25 cm
of a solution containing 1.28 g dm sodium hydroxide.
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Relative atomic masses: P = 31.0, H = 1.0, Na = 23.0, O = 16.0
Calculate the number of moles of

(i) phosphorous (V) acid that reacted

[2 marks]
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(ii) sodium hydroxide that reacted

[1 mark]
(iii) sodium hydroxide that reacted with 1 mole of the acid.

[1 mark]

(iv) Derive the equation for the reaction that occurred in Part (b) above.
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[1 mark]

(v) Outline the steps involved in carrying out the reaction described in (b) above.

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[5 marks]

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