Search our library of Chemistry questions

Top answers

Chemistry

All levels

Calculate: (a) The amount, in mol, of white phosphorus used, (b) the limiting reagent, (c) the excess amount, in mol, of the other reagent.

P₄(s) + 3OH^-(aq) + 3H₂O(l) ---> PH₃(g) + 3H₂PO₂^-(aq)
Provided for answering (a): Mass of white phosphorus: 2...

Answered by Lisajo O. • Chemistry tutor

6163 Views

Which substance is oxidised in the reaction represented by the ionic equation below? Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)

Remember OILRIG for oxidation or reduction reactionOxidisation IsLoss Reduction Is GainSo if Zinc goes from neutral charge to 2+ charge, this means it has lost 2 negative charges in electrons, so as oxida...

Answered by Ned B. • Chemistry tutor

9645 Views

Explain the need for a temperature compromise in the Haber Process: N2(g) + 3 H2(g) ⇌2 NH3(g) (ΔH = -92 kJ mol-1)

The Haber process is used to produce ammonia (NH3), so we want the equilibrium position to be as far over to the right hand side of the equation as possible to maximise the yield of NH3. As the enthalpy f...

Answered by Yulia E. • Chemistry tutor

9410 Views

Explain how electricity is conducted in a metal.

Metals have a giant metallic structure, with regular closely packed layers of positive ions in a 'sea' of delocalised electrons. What this means is that metals have a large number of positive ions, in a r...

Answered by Zeeshan K. • Chemistry tutor

8641 Views

Why does the atomic radius of an atom decrease as you go across a period?

The atomic radius is often defined as being one half the distance between the two nuclei in a homonucleur diatomic molecule. In general, there is a decrease in atomic radius as you go across a period. Thi...

Answered by Louise E. • Chemistry tutor

1583 Views