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Why do transition metals form coloured compounds?

Transition elements have 3d orbitals with the same energy level however when molecules/ligands form dative covalent bonds with a metal ion, the electron repulsion causes the 3d orbitals to split into lower a...
CC
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The reaction for the Haber process is shown below. N2(g) + 3H2(g) ⇌ 2NH3(g) What will be the effect of increasing the pressure on the amount of ammonia present at equilibrium? [1 mark]

Increase. This question is looking at a reversible reaction - the reaction can occur both forwards and backwards. Firstly to answer this question you need to appreciate that in a closed reaction the equilibr...
RV
Answered by Rebecca V. • Chemistry tutor
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Identify which 2 of the following processes involve an exothermic change: melting, boiling, freezing, deposition and sublimation

An exothermic reaction involves an output of heat, so heat is lost overall. This would mean that boiling and melting are definitely not exothermic as they involving putting in heat. Freezing is an exothermic...
ES
Answered by Ellen S. • Chemistry tutor
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What is the easiest way to calculate E cell values?

This is a calculation which students often find tricky. One fail-safe method for doing this calculation is considering E cell = E (reduced) - E(Oxidised). A more positive electrode potential means that a spe...
RD
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Why does the first ionisation energy increase across period 3?

The 1st ionisation energy is defined as the energy required to remove the outermost electron from one mole of gaseous atoms, forming one mole of gaseous 1+ ions. Moving from left to right the proton number i...
HP
Answered by Hamish P. • Chemistry tutor
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