<h3><u>Answer</u>;</h3>
4) size
<h3><u>Explanation</u>;</h3>
- The mineral’s physical properties are used in identifying minerals and are determined by its chemical composition and crystal structure.
- <u>Streak</u> is the color of the mineral in powdered form and since it is a more accurate illustration of the mineral’s color, its is a more reliable property of minerals than color for identification.
- <u>Hardness</u> is one of the better properties of minerals to use for identifying a mineral. Hardness is a measure of the mineral’s resistance to scratching.
- <u>Density</u> may be used to identify minerals. It is used to describe the amount of matter in a certain amount of space. Substances that have more matter packed into a given space have higher densities.
Answer:
Potassium
Explanation:
In group one of the periodic table both the melting and the boiling points usually decrease down the group.
Now, down the group, it's lithium that comes first, then sodium, then potassium.
Thus, among the 3, potassium is furthermost down the group by virtue of the factor it has the highest atomic number.
Therefore, we can say that potassium has the lowest boiling point among the 3.
Answer:
Vapour pressure of benzene over the solution is 253 torr
Explanation:
According to Raoult's law for a mixture of two liquid component A and B-
vapour pressure of a component (A) in solution = 
vapour pressure of a component (B) in solution = 
Where 
are mole fraction of component A and B in solution respectively
are vapour pressure of pure A and pure B respectively
Here mole fraction of benzene in solution is 0.340 and vapour pressure of pure benzene is 745 torr
So, vapour pressure of benzene in solution = 
= 253 torr
