Cs -137 has a half life of about 30 years. If 60 years pass, there is two half lives passed so 1/2 * 1/2= 1/4. Take 1/4 and multiply it with the mass given:
(1/4)*20mg=5mg left
Answer:
0.03atm
Explanation:
Given parameters:
Total pressure = 780torr
Partial pressure of water vapor = 1.0atm
Unknown:
Partial pressure of radon = ?
Solution:
A sound knowledge of Dalton's law of partial pressure will help solve this problem.
The law states that "the total pressure of a mixture of gases is equal to the sum of the partial pressures of the constituent gases".
Mathematically;
P
= P
+ P
+ P
Since the total pressure is 780torr, convert this to atm;
760torr = 1 atm
780torr =
atm = 1.03atm
For this problem;
Total pressure = Partial pressure of radon + Partial pressure of water vapor
1.03 = Partial pressure of radon + 1.0
Partial pressure of radon = 1.03 - 1.00 = 0.03atm
Answer:
it increases and is perpendicular to the motion of the wave.