Which is an ionic compound and which is a molecular compound? (picture #9)
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Answer:OK. One of the properties of an ionic compound is that it conducts a current in aqueous (water) solution.
The ionic compound is held together by virtue of the opposing charges; plus and minus. In water, they may just crumble away into solution! But if you Heat a solid piece of a salt, an ionic compound, it takes a great deal of Energy! So look at Compound Y.
WOW! 455°C to melt. That is high. To boil it? 1550°C. That is very high! Especially compared to compound X!
It melts at -90°C, and boils at 82°C. So it is X that is your molecular compound, one of covalent bonding, or sharing electrons, VERY different than the ionic compound held together by opposing charges.
Explanation: