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Chemistry

A Level

Explain how chromatography is used to separate components in a mixture.

Chromatography separates components in a mixture according to their solubility in the mobile phase and their adsobance to the stationary phase. The mobile phase is the part of the chromatography set up th...

Answered by Immy C. • Chemistry tutor

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Flask Q (volume = 1.00 x 103 cm3 ) is filled with ammonia (NH3) at 102 kPa and 300 K. The tap is closed and there is a vacuum in flask P. (Gas constant R = 8.31 J K−1 mol−1 ) Calculate the mass of ammonia

This question can be solved using the ideal gas equation, given by: PV=nRT

Rearranging the ideal gas equation gives an expression for the number of moles as

n=PV/RT

Subbing the valu...

Answered by Sebastien D. • Chemistry tutor

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What is the difference between stereoisomerism and optical isomerism?

Isomers are compounds with the same molecular formula but different arrangement of atoms in space (or structural formula). Stereoisomers (E/Z isomers) have different arangements of bonds ...

Answered by Lara I. • Chemistry tutor

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Describe and explain the electrical conductivity of lithium oxide, Li2O, and lithium in their solid and molten states.

Lithium conducts electricity in its solid and molten states. Lithium exhibits metallic bonding and as such its valence electrons are delocalised in the liquid and solid state allowing electricty to be con...

Answered by Charlie F. • Chemistry tutor

28954 Views