The answer is (b). As, vanadium is attached to five fluoride atoms, each flouride containing -1 oxidation state, hence five fluoride contains -5, to neutralize, vanadium should have +5 oxidation state.
The answer to this would be a physical change. Physical changes are changes that affect the form of a chemical substance, but not the chemical composition itself. Hope this helped!
8.3 × 106 - trust me, it's actually right. You can use the calculator to see if I'm correct. Punch in <span>8.3 × 106 = 6.6</span>
Boiling points are a measure of intermolecular forces. The intermolecular forces increase with increasing polarization of bonds. Boiling point increases with molecular weight, and with surface area.
The volume of H₂O = 5 L
<h3>Further explanation</h3>
Given
5L of H₂ and 3L O₂
Reaction
2H₂ (g) + O₂(g) ⇒2H₂O(g)
Required
The volume of H₂O
Solution
Avogadro's hypothesis:
<em>In the same T,P and V, the gas contains the same number of molecules </em>
So the ratio of gas volume will be equal to the ratio of gas moles
mol H₂ = 5, mol O₂ = 3
From equation, mol ratio H₂ : O₂ = 2 : 1, so :

mol H₂O based on mol H₂, and from equation mol ratio H₂ : H₂O=2 : 2, so mol H₂O = 5 mol and the volume also 5 L