Which polyatomic ion has a charge of ) chromate ion (2) oxalate ion (3) phosphate ion (4) thiocyanate ion

(3) phosphate ion

Explanation: A polyatomic ion is a ion which contains different atoms.

1) Chromate ion is a polyatomic ion containing chromium and oxygen with formula

2) Oxalate ion is a polyatomic ion containing carbon and oxygen with formula

3) Phosphate ion is a polyatomic ion containing phosphorous and oxygen with formula

4) Thiocyanate ion is a polyatomic ion containing sulfur, carbon and nitrogen with formula

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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