The equation you use here is
mass =moles x Mr
So:
Moles of K - 0.55mol
Mr of K - 39.1
Mass= 0.55x39.1 =21.505g
Answer: It is important to wet the filter paper in the Buchner funnel first with cold re crystallization solvent before the re crystallization mixture being filtered to minimize gaps around the edges of the filter paper which can prevent mechanical impurities from passing through. This gives better filtration where most impurities can be filtered. Furthermore, it provides good vacuum.
Hope this helps with the answer to your question
For this question the answer is c
Answer:
1.5 × 10² mL
Explanation:
Step 1: Given data
- Initial pressure of the gas (P₁): 1.9 atm
- Initial volume of the gas (V₁): 80 mL
- Final pressure of the gas (P₂): 1.0 atm (standard pressure)
- Final volume of the gas (V₂): ?
Step 2: Calculate the final volume of the gas
For an ideal gas, we can calculate the final volume of the gas using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = P₁ × V₁/P₂
V₂ = 1.9 atm × 80 mL/1.0 atm
V₂ = 1.5 × 10² mL
Since the pressure decreased, the volume of the gas increased.
