A student wants to determine whether an unknown solid is an ionic compound. He puts some in water and finds that it does not dissolve. He says that this proves the solid is ionic. Which best evaluates the student's reasoning?

Question

anonymous · Answer

He is incorrect, because water can dissolve ionic solids.

 The test proves nothing, because water dissolves all solids.

 He is correct, because polar liquids cannot dissolve ionic solids.

 The test proves nothing, because it only shows that the solid is a compound.

anonymous · Answer

@dan815 could you maybe help?

anonymous · Answer

@zepdrix can you help?

anonymous · Answer

@Compassionate

anonymous · Answer

@nincompoop

anonymous · Answer

@abb0t

abb0t · Answer

hint: Think about one of the properties of water and its shape - in terms of dipole.

abb0t · Answer

Also, think about what an ionic bond is, a positive ion bonded a negative ion. Keep that in mind also.

anonymous · Answer

I was thinking of D but wasnt sure @abb0t

abb0t · Answer

No, D is not the answer.

anonymous · Answer

OHH ok i got it its C then? @abb0t

abb0t · Answer

No.

anonymous · Answer

I feel like it is A. Since the ionic solids can dissolve in water, correct?

abb0t · Answer

For a ionic compound to dissolve, the liquid must be able to stabilize the ions that result from brekaing that bond. Positive ions are actually attracted to negative ions quite strongly, and so to break the bond, something must interfere with this attraction.

So yes, water CAN dissolve ionic species.