Answer:
1(374€×737€÷63718477284™>)2638185837+2737=12837
When concentration is expressed in molarity, this is equivalent to the number of moles of the solute per liter of solution. We are given with the amount of volume which is 239 mL or 0.239 L. However, there is no known information of the amount of solute. So, I can't give an exact answer. For sample purposes, let's just assume that there is 1 mole of KCl in the solution. The molarity would be:
Molarity = 1 moles/0.239 L = 4.184 M
Answer:
number of protons and neutrons
Explanation:
Is the combination of all forces acting on an object
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!