B. The sand increases friction by increasing roughness.
Answer:
By adding the solute in to solution boiling point is increased while freezing point is decreased.
Explanation:
When solute in added into the solvent the boiling point of solvent increases for example,
Water is boiled at 100 °C, when sodium chloride is added its boiling point increased. Ions of salt interact with solvent and prevent the water molecules to escape from the surface and form gas molecules. In order to make it boiled solution must be heated above 100 °C.
But there is different case with freezing point. Freezing point is the state in which substance converted into the solid. At given temperature when solute is added into the solvent it prevent the formation of solid. It required time to decrease the temperature first and as the temperature is decreases solid is formed.
Answer:

Explanation:
The volume and amount are constant, so we can use Gay-Lussac’s Law:
At constant volume, the pressure exerted by a gas is directly proportional to its temperature.

Data:
p₁ = 1520 Torr; T₁ = 27 °C
p₂ = ?; T₂ = 150 °C
Calculations:
(a) Convert the temperatures to kelvins
T₁ = ( 27 + 273.15) K = 300.15 K
T₂ = (150 + 273.15) K = 423.15 K
(b) Calculate the new pressure

(c) Convert the pressure to atmospheres

C. released or absorbed.
When the energy is released the reaction is called exotermic reaction
When the energy is absorbed, the reaction is called endothermic reaction
An example of exotermic reaction is between water and H2SO4