Given the known compounds--- CO2,KF,MgO,CaCL2,Na2O,Ga2O3 and AICl3- predict tbe formula for the following combinations of elements.

1.Si and O ____
2.Ba and S______
3.K and S________
4.B and F_________
5.Li and Br________
6.Sr and O__________

Thanks for the help!

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