Draw the lewis structure, including typical contributions to the resonance structure (where appropriate, allow for the possibility of octet expansion, including double bonds in different positions), for (a) periodate ion; (b) hydrogen phosphate ion; (c) chloric acid; (d) arsenate ion.

check attached diagram

Explanation:

In order to draw a lewis structure for any ion,molecules or compounds, the following step must be followed;

FIRST STEP: select a central atom, the central atom should be the most electronegative as compare to other atoms in the ion, molecule or compounds.

For (a),(b), (c) and (d); Iodine,Phosphorus, Chlorine and Arsenic respectively.

SECOND STEP: Join this central atom to other atoms with a single bond

THIRD STEP: calculate the number of π electron using the formula below;

P= 6n +2 - V. Where V= valence electron, p= number of pie electron, n= number of atom

V can be calculated;

V= (6+6+6+6+5+1) - (-2)

=32

FOUTH STEP: complete the structure drawing it resonance

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the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia

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