Bynari means that the compound is formed by two kind of elements.
You have listed three ions, V 5+, Cl - and O 2-.
Binary ionic compounds are formed by a positive ion and a negative ion, so the possible ionic compound formed by the listed ions are:
1) VCl5, where the number 5 next to Cl is a subscript.
2) V2O5, where the number 2 next to V and the number 5 next to O are subscripts.
Subscripts are used to indicate the number of atoms of each element in the formula.
So, the empirical formula searched are VCl5 and V2O5.
I can give you other examples with more ions.
Ca (2+) and S(2-) => Ca2S2 => CaS
Na(+) and F(-) => NaF
Cs(+) and Br(-) => CsBr
Answer:
The food coloring mixes through the hot water faster than it mixes with the cold water. This is because in hot water, thewater molecules have more energy and are moving faster than the molecules of cold water. This makes it easier for the dye to get mixed throughout the hot water.
Answer: Wavenumber of the radiation emitted is 
Explanation:
The relationship between wavelength and energy of the wave follows the equation:

where,
E = energy of the radiation = 
h = Planck's constant = 
c = speed of light = 
= wavelength of radiation = ?
Putting values in above equation, we get:


Thus wavenumber of the radiation emitted is 
Answer:
B
Explanation:
Oil > Animals > Plants > Chemicals