Compared to a 2.0 m aqueous solution of nacl at 1 atmosphere, a 3.0 m aqueous solution of nacl at 1 atmosphere has a
(1) lower boiling point and a higher freezing point
(2) lower boiling point and a lower freezing point
(3) higher boiling point and a higher freezing point
(4) higher boiling point and a lower freezing point

The correct answer is option 4. A 3.0 M aqueous solution of NaCl has a higher boiling point and a lower freezing point than a 2.0 M aqueous solution of NaCl where both are at 1 atmosphere. This is explained by the colligative properties of solutions. For the two properties mentioned, the equation for the calculation of the depression and the elevation is expressed as: ΔT = -Km and ΔT = Km, respectively. As we can see, concentration and the change in the property has a direct relationship.

acids can dissolve grease but not oil

Explanation:

Oil

Most acids do not dissolve oil because the two types of substances differ chemically. When mixed, the two form two separate layers as water and oil does. 

Grease

Muriatic acid, gasoline work to remove grease. Sulfuric acid can liquefy grease.