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Chemistry

A Level

How can you determine the shape of water?

Water consists of two hydrogen atoms covalently bonded to an oxygen atom, the atoms oxygen has 6 outer shell electrons, and wach hydrogen donates one, this results in the structure having 8 electrons, mea...

Answered by JOSHUA M. • Chemistry tutor

1742 Views

What are the oxidation numbers of each element in these examples: a) H2SO4 b) N2 c) NH4+

a) H₂SO₄ANSWER: H: +1 S: +6 O: -2 b) N₂ANSWER: N: 0 (all elements not within a compound have an oxidation number of 0 eg I₂, O₂, K) c) NH₄

Answered by Georgia B. • Chemistry tutor

1781 Views

Would you expect a calcium ion to be bigger, smaller or the same size as a calcium atom? Give TWO reasons to explain your answer.

Calcuim is in group two which means when it forms an ion it will donate its two outer elections, this means a calcium ion will be smaller as it has one less shell of electrons.

Answered by Urma C. • Chemistry tutor

13359 Views

State and explain the effect of the following on the rate of a reaction: a) increasing temp b) increasing pressure c) increasing concentration of ONE reactant d) adding a catalyst. In each case state what will happen to the rate constant, k.

a) will increase

greater collision energy

so greater chance of activation energy being exceeded

so greater fraction of successful collision...

Answered by Joseph P. • Chemistry tutor

3760 Views

When you are given a table of half cells with values for electrode potentials, how do you find the strongest oxidising and reducing agent?

Possibly the easiest way to do this is by thinking about what the value of Electrode Potential means. The more positive the Electrode Potential, the greater the tendency of the species in the equation to ...

Answered by James S. • Chemistry tutor

6192 Views