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Chemistry

A Level

Why does magnesium have a higher melting point than sodium?

Both sodium and magnesium have metallic bonding between atoms. Outer electrons become delocalised and float freely between the positive ions. The positive ions attract the negatively charged electrons so ...

Answered by Suzie C. • Chemistry tutor

46513 Views

Thinking about the periodicity of the period 3 elements, explain the structure of the Sodium and Phosphorus Oxides and the acid-base behaviour of the Oxide solutions.

Electronegativity increases across a period because the atomic radius decreases (i.e. the valence electrons are closer to the nucleus and experience a higher attraction). This is because there are more pr...

Answered by Natalie M. • Chemistry tutor

5867 Views

Calculate the concentration, in mol dm-3, of a solution of chloric (I) acid, HOCl , which has a pH of 4.23. Chloric acid is a weak acid, with Ka = 3.72 x 10^-8

[H+] = 10^-4.232) [H+]^2 = Ka x [HA]3) [HA] x Ka = (3.467368505 x 10^-9)4) [HA] = 0.0932

Answered by Afshaun A. • Chemistry tutor

6473 Views

Explain, in terms of atomic energy levels, how an atomic emission spectrum is formed

Absorbed energy results in electron excitation. De-excitation then occurs, whereby electrons fall back down to the ground state. Energy levels are quantised, therefore each line represents a specific freq...

Answered by George C. • Chemistry tutor

2517 Views

3-Methylpent-2-ene (CH3CH=C(CH3)CH2CH3) reacts with Hydrogen Chloride(HCl) forming a major and minor product. Please name the reaction, draw the mechanism for the formation of the major product and briefly explain why there is a major and a minor product.

This is an example of electrophilic addition.(It's easier to explain with the mechanism drawn) The mechanism proceeds by electrophilic attack of the Hydrogen in HCl originating from the double bond in 3-m...

Answered by Edward H. • Chemistry tutor

12489 Views