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Atoms and reactions

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Question 55

2.36 g of trimethylamine gas, (CH3)3N(\text{CH}_3)_3\text{N}(CH3​)3​N (Mr=59.0M_{\text{r}} = 59.0Mr​=59.0), is reacted with 80 cm3 of 0.75 mol dm-3 hydrobromic acid forming a solution of trimethylammonium bromide.

(CH3)3N(g)+HBr(aq)→(CH3)3NH+(aq)+Br−(aq) (\text{CH}_3)_3\text{N}(\text{g}) + \text{HBr}(\text{aq}) \rightarrow (\text{CH}_3)_3\text{NH}^+(\text{aq}) + \text{Br}^-(\text{aq}) (CH3​)3​N(g)+HBr(aq)→(CH3​)3​NH+(aq)+Br−(aq)

What is the concentration of trimethylammonium bromide in mol dm−3\text{mol dm}^{-3}mol dm−3?

A

0.040.040.04

B

0.250.250.25

C

0.500.500.50

D

0.750.750.75

Markscheme

Atoms and reactions Questions

  1. A Level
  2. /Chemistry
  3. /Atoms and reactions

199 exam-style questions on OCR A A Level Chemistry Atoms and reactions, covering Atomic structure and isotopes, Compounds, formulae and equations, Amount of substance, Acids, and Redox. Each one has a worked solution and a mark scheme showing where the marks go.

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