Answer:
180psi
Step-by-step explanation:
Step one:
given data
P1= 900 psi
T1= 350°C
P2=?
T2=70°C
Required
The final pressure P2
<em>Gay-Lussac's Law: The Pressure Temperature Law. This law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature. With an increase in temperature, the pressure will go up</em>
Applying the expression
P1/T1= P2/T2
substitute:
900/350= P2/70
2.57=P2/70
cross multiply
P2= 2.57*70
P2=180psi
17.4736843 or 17 remainder 45
This problem can be represented through the following equation
A = A₀(1/2)^t/h
where
A-----------> is the amount of substance left after time t
A₀ ----------> is the original amount---------> 2 g
h-------------> is the half-life-----------> 8 days
for A=0.04 g
t=?
0.04 = 2(1/2)^t/8
0.02 = (1/2)^t/8
Take ln on both sides:
ln(0.02) = ln [(1/2)^t/8]
ln(0.02) = (t/8)(ln 1/2)
t = 8*ln(0.02)/ln(1/2)
t = 45.15 days
the answer is 45.15 days