Top answers

Chemistry
A Level

Part a) Draw the mechanism of the attack of CN- on CH3COCH3 in the presence of HCN Part b) Explain why the product of this reaction does not rotate the plane of plane polarised light

Part a) 1 mark : Show the nucleophilic attack of CN- at the carbonyl forming the O-1 mark : Show the protonation of the O- via the deprotonation of HCNPart b)1 mark: Student has identified that the interm...

Answered by Noah H. Chemistry tutor
2826 Views

A chemist synthesised two solutions A and B, they know one solution is an aldehyde and the other a ketone. Suggest how the chemist could identify which is which and describe any observations they would make

Tollens reagent could be used to identify the the solutions A and B, as the aldehyde solution will oxidise to a carboxylic acid and a ‘silver mirror’ will be observed. Ketones cannot be oxidised further a...

Answered by Hugo J. Chemistry tutor
1390 Views

Why is the Mg2+ ion smaller in radius than the Na+ ion?

The magnesium ion is in group two of the periodic table, whereas sodium is in group one. This means that magnesium has one more proton than the sodium ion, so it has a more positive core. Both ions have t...

Answered by Olivia D. Chemistry tutor
8207 Views

The enthalpy of combustion of ethanol is −1371 kJ mol−1 . The density of ethanol is 0.789 g cm−3 . Calculate the heat energy released in kJ when 1 dm3 of ethanol is burned.

1 dm3 of ethanol is equal to 1000 cm3, so the mass of ethanol used is =density x volume = 0.789 g cm-3 x 1000 cm3 = 789gMolar mass of ethanol = (2x12)+(6x1) +(1x16)= 46 g mol-1Moles of ethanol = mass/mola...

Answered by Sophie L. Chemistry tutor
13401 Views

Why are complex ions containing transition elements coloured?

Firstly a transition element is an element which forms one or more stable ions with incompletely filled d orbitals.Ligands are charged or neutral, ions or molecules, which form coordination bonds with a c...

Answered by Josephine R. Chemistry tutor
7849 Views

We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences