How do you find the formulas of these compounds? i’m lost

1. Sodium hydroxide formula NaOH

6. Copper ii carbonate formula CuCO3

9. Iron ii oxide formula  FeO

I was going to do it all, but you could use some websites to look it up.

http://www.endmemo.com/chem/chemsearch.php

https://formulas.tutorvista.com/chemistry/chemical-compound-formulas.html

state the principle of separating two immiscible liquids by separating funnel. describe an activity with diagram to separate a mixture of water and kerosene oil. answer: immiscible layers separate out in layers depending on their densities in separating funne

confused

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