Question

1. in order for a solute to be dissolved in water it has to

a) be an ionic compound

b) be a polar compound

c) be a nonpolar compound

d) A and B

2. Hydrophobic exclusion drives the spontaneous formation of which of the following

a) cell membranes

b) proteins

c) oil layer in salad dressing

d) all of the above

Answer 1

1. in order for a solute to be dissolved in water it has to

d) A and B

Water is a polar solvent , so molecules are attracted to other polar molecules. Ionic compounds are also soluble in water, Sodium Chloride (NaCl)- here water molecules interact with the sodium and chloride ions. Many substances can dissolve in water, that's the reason, water is called as the universal solvent. The energy released when the ions interact with water molecules can be used for the energy required for breaking down the ionic bonds and the energy required to break down the water molecules.

2.  Hydrophobic exclusion drives the spontaneous formation of which of the following

c) oil layer in salad dressing

The hydrophobic nature of lipids is driven by the bonds between carbons and hydrogens atoms but the bonding between carbon and hydrogen atoms is not polar. That means electrons are shared equally between the carbons and the hydrogens covalently and no partial charges are found. Moreover, tristearin ( triacylglycerol) is insoluble in water. When pour in water, tristearin will form a separate layer from the water based vinegar in salad dressing.