Answer:
The amount of drug left in his body at 7:00 pm is 315.7 mg.
Explanation:
First, we need to find the amount of drug in the body at 90 min by using the exponential decay equation:

Where:
λ: is the decay constant = 
: is the half-life of the drug = 3.5 h
N(t): is the quantity of the drug at time t
N₀: is the initial quantity
After 90 min and before he takes the other 200 mg pill, we have:

Now, at 7:00 pm we have:

Therefore, the amount of drug left in his body at 7:00 pm is 315.7 mg (from an initial amount of 400 mg).
I hope it helps you!
1.75 moles ChCl3 x (6.02 x 10 ^-23) / 1 mole = 1.0535 x 10^-22 atoms.
hope this was helpful :)
Answer:
vapour pressure I's crushing the bottle
mark brainliest
Answer:
3.31 atm.
Explanation:
- Gay-Lussac's law states that for a given mass and constant volume of an ideal gas, the pressure exerted on the sides of its container is directly proportional to its absolute temperature.
∵ P α T.
<em>∴ P₁T₂ = P₂T₁.</em>
P₁ = 3.00 atm, T₁ = 20.0 °C + 273.15 = 293.15 K.
P₂ = ??? atm, T₂ = 50.0 °C + 273.15 = 323.15 K.
<em>∴ P₂ = (P₁T₂)/T₁</em> = (3.00 atm)( 323.15 K)/(293.15 K) = <em>3.307 atm ≅ 3.31 atm.</em>