Answer:
The volume of gas is 58.22 L which will occupy at 250.°C and 680 mm Hg pressure.
Explanation:
Given:
Temperature = 27°C
To make it into kelvin = 27+273
= 300K
Pressure =740mm Hg
to make it in atm. = 
= 0.973atm
n = 2.3 moles
Volume of gas =?
As we know according to the formula
PV = nRT

On substituting the values
= 
= 58.22 L
Therefore, 58.22L volume of gas will occupy at 250.°C and 680 mm Hg pressure.
I would say the first three. But I'm not 100% sure. I'm truly sorry if it's wrong
Answer:
True
Explanation:
The physical and chemical properties of a substance depend on the nature of intermolecular forces between its molecules. For instance, water has a high boiling point because of hydrogen bonding between water molecules. Liquid water is denser than ice because of the difference in the nature of hydrogen bonding in liquid water and ice.
Answer:
Fig 3 is a mixture
Explanation:
Fig 1 has just one kind of atoms.
fig 2 shows 2 atoms of the same kind bonded together (compound)
fig 4 shows atoms of 2 different kinds bonded together (compound)
only in fig 3 we see uneven distribution of two kinds of atoms. By definition a mixture contains two or more kind of substances randomly arranged. So fig 3 shows arrangement of mixture