They are described through the use of four physical properties or macroscopic characteristics: pressure, volume, number of particles (chemists group them by moles) and temperature.
Answer: The volume occupied by 2.50 moles of 
gas at STP is 56.0L
Explanation:
According to ideal gas equation:
P = pressure of gas = 1 atm (at STP)
V = Volume of gas = ?
n = number of moles = 2.50
R = gas constant =
T =temperature =
(at STP)
Thus the volume occupied by 2.50 moles of gas at STP is 56.0L
Answer:Amplitude in a longitudinal wave
Explanation:Wave amplitude of a longitudinal wave is the distance between particles of the medium where it is compressed by the wave. Wave amplitude is determined by the energy of the disturbance that causes the wave. A wave caused by a disturbance with more energy has greater amplitude.
The element which is least likely to undergo a chemical reaction is (4) neon.
The reason for this is because neon is a noble gas, which means that it doesn't react with other elements as well.
