The answer is; liquid phase
The characteristics described in the question are those of a liquid. The forces between liquid particles are weaker than the forces between solid particles because the particles are further apart. The particles are not held in a fixed position in the structure hence it can flow and take the shape of the container in which it is in.
A. Cesium because reactivity of alkali metals increases from the top to the bottom of the group.
Answer:
The molar mass of the gas is 44.19 g/mol
Explanation:
Amount of sample of gas = m = 13.5 g
Volume occupied by the gas = V = 5.10 L
Pressure of the gas = P = 149.83 KPa
1 KPa = 0.00986 atm
P = 
Assuming M g/mol to be the molar mass of the gas
Assuming the gas is behaving as an ideal gas

The molar mass of gas is 44.19 g/mol