Water is a great solvent of other polar or ionic substances. It is often called the universal solvent because water is so abundant, and it can dissolve so many different substances. Watch the following animation showing how water dissolves the ionic compound sodium chloride NaCl.
Source: Dissociation of Salt, kosasihiskandarsjah, YouTube
What element in the water molecule is attracted to the positively charged sodium ion?
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Oxygen is attracted to the negatively charged chlorine ion because oxygen has a partial negative charge.
What part of the water molecule is attracted to the negatively charged chlorine ion?
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Hydrogen is attracted to the negatively charged chlorine ion because it has a partial positive charge.
If water was non-polar (like CO2), could it dissolve NaCl? Explain your answer.
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Non-polar compounds like CO2 are not attracted to the charges on ionic compounds; therefore, they cannot dissolve in NaCl.
Water is the universal solvent, but can it dissolve everything? Watch the following video.
Source: Science Fair Magic, Oil and Water Transposition, edumazement, YouTube
As a rule "like dissolves like." This saying means that polar solvents dissolve polar and ionic solutes. Non-polar solvents dissolve non-polar solutes. Based on your observations from this video, is oil polar or non-polar?
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We know that oil is non-polar because it does not dissolve in the water.