Top answers


A chemist has 3 beakers, each containing a pure sample of acetone (2-propanone), isopropanol (2-propanol) and propanal. Using chemical techniques, suggest how the chemist may be able to determine which beaker contains which sample. [4]

Brady's reagent is an orange solution of 2,4-dinitrophenylhydrazine which reacts with carbonyl containing functional groups to produce an orange precipitate (2,4-dinitrophenylhydrazone derivative of the carb...
SM
Answered by Stephen M. Chemistry tutor
2606 Views

State and explain the evidence for the delocalisation of electrons in benzene (6 marks)

Benzene does not decolourise bromine water, showing it does not undergo electrophilic addition reactions as the delocalised pi structure is very stable. All of the carbon-carbon bond lengths are the same; th...
RA
Answered by Romi A. Chemistry tutor
4509 Views

An unknown gas from a reaction is contained in a 2 litre beaker, at standard atmospheric pressure and a Temperature of 25 Celsius. Calculate the number of moles of the gas.

PV=nRT n=PV/RT=(1.01*10 5 0.002)/(8.31 298)=0.0816 moles
JM
Answered by James M. Chemistry tutor
2107 Views

Can you describe four variables which affect the rate of a chemical reaction and how they affect the rate?

Temperature: A higher temperature increases the rate of a reaction by increasing the number of particles with enough energy to take part in a reaction. 2) Particle size: The smaller the particle size the gre...
SS
Answered by Steven S. Chemistry tutor
2744 Views

In the presence of ultraviolet radiation, cyclohexane reacts with bromine. A mixture of cyclic products are formed, including C6H11Br. Discuss each step of this reaction providing equations to show the mechanism.

INITIATION: Br 2 --> 2Br . The breaking of the Br 2 bond from ultraviolet radiation forms two radicals, as one electron from the bond pair goes to each bromine atom. This is called homolytic fission. PROP...
LK
Answered by Lisa K. Chemistry tutor
19600 Views