AS 90944 Rate of Reaction Homework
Watch the tutorial on rate of reaction before attempting your homework
AS 91161 Carry out a quantitative analysis. titrations
Play the presentation Chemical equations and calculations. Pay particular attention to the worked example before doing the example at the end of this post
Example to be handed in tomorrow
Hydrochloric acid solution was titrated with standard sodium hydroxide solution.
Before the titration the acid was diluted by making 1ml of solution up to 20ml(1:20) in a volumetric flask
20 ml samples of the acid in conical flasks were titrated by running standard sodium hydroxide solution ( 0.15 molL-1 concentration) in from a burette using phenolphthalein indicator
Titration Results
Volume of hydrochloric acid=20ml
|
Titration |
rough |
titration 1 |
titration 2 |
titration 4 |
titration 5 |
|
Final volume (ml) |
26.35 |
49.60 |
24.50 |
50.00 |
47.80 |
|
Initial volume (ml) |
00.00 |
25.20 |
00.20 |
27.00 |
23.30 |
|
Titre (ml) |
26.35 |
24.40 |
24.30 |
23.00 |
23.50 |
On your own paper:
- write the heading Titration Calculation
- Copy the table of results beneath
- select three concordant results and calculate the average titre
- Write down the balanced chemical equation for the reaction
- Use the method you have been shown to calculate the concentration of the hydrochloric acid
As 91164 Structure bonding and thermochemistry retest
1 CommentAS 91164 Structure and bonding:Practice question 2, diamond and graphite
Look through the presentation on diamond and graphite before tackling the question based on one in the 2011 paper.
This question is based on the 2011 paper.
AS 91164 Structure and bonding:Practice question 1
The structurfe of quartz
Silicon and oxygen atoms are arranged in a three dimensional covalent network. A portion of such a framework is shown here. In this arrangement, the stoichiometry is reduced to SiO2, (each silicon has a half share of four oxygens) which is often called silica. A collection of small pieces of quartz is sand.
Tackle both questions on quartz and zinc below.
