How to do titrations

andysan64
Mind Map by andysan64, updated more than 1 year ago
andysan64
Created by andysan64 almost 6 years ago
114
4

Description

How to do an example titration.

Resource summary

How to do titrations
1 25cm3 of sodium hydroxide (NaOH) at 1.5 mol/dm3 neutralises 21.5cm3 of hydrochloric acid (HCl). Find the concentration of the acid in moles per decimetre cubed (mol/dm3). Decimetres cubed is the same thing as litres
1.1 So we know that in 1 litre of NaOH, we've got 1.5 moles. How much do we have in one millilitre?
1.1.1 1ml = 15/1000 = 0.0015 moles per ml (because there are 1000 millilitres in a litre, we divide by 1000.)
1.1.1.1 But we don't have 1 ml of it, we have 25 ml of it, so we multiply by 25. 25 x 0.00515 = 0.0375 moles. Now, this tells us how much stuff we've got in each chemical.
1.1.1.1.1 Because there are the same number of moles in each chemical. If there weren't, and the ratios were different, we would simply multiply or divide as needed.
1.1.1.1.2 But, again, we don't have equal amounts of each substance, so we need to first find out the concentration of 1 millilitre (cm3) of HCl. 0.0375/21.5 (because that's how much HCl we've got) = 0.0017441 moles in a cm3 of HCl.
1.1.1.1.2.1 The question is asking for the concentration of the HCl in moles per decimetre cubed, so we multiply by 1000, because that's how many millilitres we've got in a litre. 0.0017441 x 1000 = 1.74 mol/dm3
1.2 First, we need to balance the equation: NaCl + HCl ==> NaCl + H2O
1.2.1 From this, we can see that the ration of sodium hydroxide to hydrochloric acid is 1:1, so for each mole of NaCl, there is 1 mole of HCl.
Show full summary Hide full summary

Similar

GCSE - AQA: C1.1 The Fundamental Ideas in Chemistry
Olly Okeniyi
GCSE AQA Chemistry 1 Fuels & The Environment
Lilac Potato
Chemistry 6 Extracting Vegetable Oil Core GCSE AQA
Chloe Roberts
GCSE AQA Chemistry 2 Salts & Electrolysis
Lilac Potato
Crude Oils and others quiz
Dale George
Test for positive ions
bella.mort
Acids and Bases
Sarah Egan
Acids and Bases quiz
Derek Cumberbatch
exothermic and endothermic reactions
janey.efen
Using GoConqr to study science
Sarah Egan
GCSE AQA Biology - Unit 2
James Jolliffe