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Chemistry

A Level

Explain the principle behind chemically reactive and inert molecules

Electronegativity.
Molecules with atoms which possess an almost full outer shell will always be seeking to draw in the extra electron(s) to fill up their outer shells.Likewise molecules with atoms wh...

Answered by Irtiza S. • Chemistry tutor

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Explain why atomic radius decreases across a period

As you go along a period, there is an increasing number of protons in the nucleus of each atom meaning that the nucleus has an increasing positive charge.This means that the electrons are puller closer to...

Answered by Tutor406540 D. • Chemistry tutor

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In the reaction CO(g) + 2H2(g) <--> CH3OH(g), explain why an increase in pressure increases the yield of methanol

Increasing the pressure shifts equilibrium towards the side with fewer moles of gas, so in this reaction the equilibrium will move to the right. Hence, a shift towards the right hand side...

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Explain why phenol is nitrated more readily than benzene.

Phenol has a lone pair of electrons on the O group which can be delocalised into the benzene Pi system2) This delocalisation increases the electron density in the pi system compared to benzene3) Thi...

Answered by Daniel B. • Chemistry tutor

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Explain why water molecules form on average two hydrogen bonds per molecule, whereas ammonia molecules (NH3) form only one.

A hydrogen bond requires both a lone pair of electrons on a O, N or F atom and a hydrogen atom. In water there are two lone pairs and two hydrogen atoms, allowing the formation of two hydrogen bonds. In a...

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