I believe the answer is A. However, I would double check the formula.
Answer:
What do you think causes some rock types to have higher densities than others? (Assuming there are no air pockets in the rock, the types of minerals will determine the density. Granite contains lots of quartz and feldspar - both fairly light minerals, whereas basalt and gabbro are made of heavier minerals.)
Explanation:
The correct answer is - b. If available resources decrease, then competition will increase.
All living organisms in an ecosystem are specialized in accordance to the living conditions and the food sources available. If a given ecosystem experiences prolonged drought, than the resources will decrease. With a decrease in resources, the living organisms will find themselves in a situation of scarcity. That will lead to a much increased competition, with both organisms of different species, and members of the same species. That will most likely lead to a situation where only the fittest will survive, while the weaker members of the species will probably die in that period of prolonged drought as they will not be able to get the resources they need to survive.
Answer: vapor pressure of solution will be less than that of the pure solvent
Explanation:
Vapor pressure of a liquid is defined as the pressure exerted by the vapors in equilibrium with the liquid/solution at a particular temperature.
So, when a non-volatile solute is added to a solvent then its molecules align at the surface of liquid. As a result, less number of solvent molecules will escape from the solution. Thus, there will be decrease in vapors and thus the vapor pressure decrease.
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
where,
= vapor pressure of pure solvent
= vapor pressure of solution
= mass of solute
= mass of solvent
= molar mass of solvent
= molar mass of solute
