Question

An element forms an oxide, E₂O₃, and a fluoride, EF₃.(a) Of which two groups might E be a member?

Answer 1

a) The E might belong to group 13.

As the formula of a chemical compound is derived by the cross multiplication of the valency of the atoms. As formula of the given oxide is  and valency of O atom is -2, therefore valency of element E must be +3 in order to obtain E2O3.

Also, in EF3, the valency of E will be +3 because there are three atoms of fluorine who has an individual valency of -1. Thus, e will have the valency of +3.

The Group 13 is the boron group which has the following elements:

• Boron
• Aluminium
• Gallium
• Indium
• Thallium

All these elements have the valency of +3.

To know more about Valency, refer to this link:

brainly.com/question/12717954

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