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Chemistry

A Level

How can you deduce the order of the reaction with respect to the reagent based on the graph of its concentration against time?

For the zeroth order reaction, the graph would be a straight line with a negative gradient. For the first order reaction, the graph would be a curve with constant half-life. That means the time for the co...

Answered by Joanna U. • Chemistry tutor

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Methylpropene reacts with hydrogen bromide to form 2-bromo-2-methylpropane, draw the mechanism and state the major products.

2-bromo-2-methylpropane

Answered by Mia B. • Chemistry tutor

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20cm3 of 0.5moldm-3 of HCL is diluted by adding 15cm3 of water. This diluted solution is titrated against a 0.3moldm-3 solution of NaOH. What is the volume of the NaOH in cm3 required to reach the endpoint of the titration?

We need to calculate how many moles of HCl are being titrated. This is the volume in dm3 times the concentration (trick: you can do dimensional analysis if unsure of the formula): number of moles of HCl =...

Answered by • Chemistry tutor

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The enthalpy change for the forward reaction is -92kJ/mol. State and explain how the value of Kp would change if the temperature was increased.

The value of Kp would decrease.Using Le Chatelier's principle the position of equilibrium would shift so as to oppose the change.The endothermic (backward) reaction would therefore be favoured in order to...

Answered by Fin M. • Chemistry tutor

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Give and explain 2 of the anomalous properties of ice caused by hydrogen bonding

Compared to water ice is less dense this is due to hydrogen bonds in the open lattice holding the H₂O molecules apart whereas in liquid form the hydrogen bonds break allowing the molecules of w...

Answered by Morgan T. • Chemistry tutor

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