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Chemistry

A Level

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

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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

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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

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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

10286 Views

Consider the transition metal complex [CoCl3(CO)3]. What is a) The oxidation state of the metal centre. b) The dn configuration of the metal centre. c) The co-ordination number of the metal centre.

a) +3. Cl ligands carry a negative charge while CO ligands are neutral so the all together the ligands have a charge of -3. Since the complex is neutral overall, the metal must cancel out the charge of t...

Answered by Robert S. • Chemistry tutor

6960 Views