L
mol/dm³ is measure for molarity
To find moles in this sample, you would divide grams by molar mass of ethyl alcohol
(18.0g)/(46.07g/mol) = 0.391mol C2H6O
Answer:
286 kPa
Explanation:
Boyles law states that volume of gas is inversely proportional to pressure o gas for a fixed amount of gas at constant temperature
P1V1 = P2V2
where P1 is pressure and V1 is volume at first instance
P2 is pressure and V2 is volume at the second instance
substituting the values in the equation
229 kPa x 4.0 L = P2 x 3.2 L
P2 = 286.25 kPa
the new pressure is 286 kPa
The decay of dead things and soil
Answer:
Option C is correct.
t = 1.95 billion years.
Explanation:
Radioactive decay follows a first order reaction kinetics.
On solving the dynamic equation (the differential equation), this is obtained
C(t) = C₀ e⁻ᵏᵗ
C(t) = amount of radioactive material remaining after time t = 37.5%
C₀ = Initial amount of radioactive material = 100%
t = time that has passed = ?
k = decay constant.
For a first order reaction, the decay constant is related to the half life through the relation
k = (In 2)/T
T = half life = 1.38 billion years
k = (In 2)/1.38
k = 0.5023 per billion years.
C(t) = C₀ e⁻ᵏᵗ
0.375 = e⁻ᵏᵗ
e⁻ᵏᵗ = 0.375
In e⁻ᵏᵗ = In 0.375 = -0.981
-kt = -0.981
t = (0.981/0.5023) = 1.95 billion years.
Hope this Helps!!!
