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GCSE

Explain the collision theory.

In order to react, particles must collide with sufficient energy. Particles with a temperature above 0K are always moving and colliding with each other.

Answered by Nick S. • Chemistry tutor

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In a titration, 45.0 cm^(3) of 0.100 mol dm^(-3) sodium hydroxide solution is exactly neutralised by 40.0 cm^(3) of a dilute hydrochloric acid solution. Calculate the concentration of the hydrochloric acid solution in mol dm^(-3).

First of all, summarise everything that you know in a table or in brief notes:NaOH, 45 cm^(3), 0.1 mol dm^(-3)HCl, 40 cm^(3)The first thing that you need to do is to find the number of moles of NaOH. This...

Answered by Lauren J. • Chemistry tutor

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What is the difference between Ionic and Covalent Bonding

IonicIonic bonding happens between metals and non-metals. The electrons in ionic bonding are given or taken. For example, Sodium + Chlorine --> Sodium Chloride. (Na + Cl --> NaCl ) ...

Answered by Ananya T. • Chemistry tutor

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Explain the trend in reactivity of the elements in Group 7.

The Halogens decrease in reactivity as you descend through the group. The atoms increase in size and Mr as you go down the group. Therefore their outer electrons are further away from the positive charge ...

Answered by Kirsten S. • Chemistry tutor

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In terms of electrons, what happens when magnesium atoms react with oxygen atoms to produce magnesium oxide?

Magnesium loses two electrons which are transferred to the oxygen atom (so oxygen gains two electrons). In this way, both magnesium and oxygen will acheive a stable full outer shell of electrons. The elec...

Answered by Reka K. • Chemistry tutor

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