Answer:
Explanation:
Often, a worker will need to change the concentration of a solution by changing the amount of solvent. Dilution is the addition of solvent, which decreases the concentration of the solute in the solution. Concentration is the removal of solvent, which increases the concentration of the solute in the solution. (Do not confuse the two uses of the word concentration here!)
In both dilution and concentration, the amount of solute stays the same. This gives us a way to calculate what the new solution volume must be for the desired concentration of solute. From the definition of molarity,
molarity = moles of solute / liters of solution
we can solve for the number of moles of solute:
moles of solute = (molarity)(liters of solution)
A simpler way of writing this is to use M to represent molarity and V to represent volume. So the equation becomes
moles of solute = MV
Because this quantity does not change before and after the change in concentration, the product MV must be the same before and after the concentration change. Using numbers to represent the initial and final conditions, we have
M1V1 = M2V2
as the dilution equation. The volumes must be expressed in the same units. Note that this equation gives only the initial and final conditions, not the amount of the change. The amount of change is determined by subtraction
Single-replacement reaction. hope it helped <3
Almost 30 years after the clean water act was passed in the US, the percentage of surface water considered safe for fishing and swimming had increased from 36% to 60% which is almost twice the original value. Certain programs and policies were implemented as part of the act.
Answer:
I believe it would be 30, 100, and 1. You count them, and they're significant figures. The decimals are an estimate and cannot be measure exactly. That is what I've learned, not sure what you're learning but hopefully it helps...
Explanation:
Basic explanation is when you count, that's an exact count. You're not estimating. That's real. But for measuring something, you wouldn't have a precise answer because it could go on forever (like Pi)... this is just what i'm assuming.
