PLS help
Given Scandium +5, make a proper ionic bond with oxygen.
a
Sc5O2
b
ScO
c
Sc5O
d
Sc2O5

Sc2O5

Explanation:

We must first consider the relative valencies of the elements. Recall that the formulae of the compound must involve an exchange in the valencies of the two combining species. Hence the first step in solving the problem must be to put down the individual valencies of the both elements then exchange thief valencies to obtain the actual formula of the compound formed by a combination of the both species as we shall show below;

Oxygen=2

Scandium= 5

When the both exchange their valencies

Scandium= 2

Oxygen=5

Hence the formula of the compound will be Sc2O5

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance