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?

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.

Question

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?

 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.

jfraser · Answer

What do you think it might be?

anonymous · Answer

I think it may be A

jfraser · Answer

can you give a specific example that would prove the point?

anonymous · Answer

Well I don't believe that water can dissolve into ISONIC solids..i'm kind of confused honestly

jfraser · Answer

it's not that water dissolves INTO ionic solids, it's that water can dissolve ionic solids into them

anonymous · Answer

I'm still confused.. @JFraser

jfraser · Answer

when you throw a little bit of salt into water, does the water dissolve into the salt, or does the salt dissolve into the water?

anonymous · Answer

im confused with the question not with what you said

jfraser · Answer

ok, then the answer is A. the substance does not dissolve in water, but he's incorrect in his logic

anonymous · Answer

so I was correct?

jfraser · Answer

the ugly truth is that not ALL ionic substances dissolve in water, but a lot of them do. the question isn't that great, but you are correct