Dillution/solution prep + concentration

Question 1

Q5: How do you calculate moles of solute?

Answer 1

A5: n = c × V

Question 2

Q8: What is dilution?

Answer 2

A8: Reducing the concentration of a solution by adding more solvent. (the actual mols remains the same)

Question 3

Q9: What is the dilution formula?

Answer 3

A9: c₁V₁ = c₂V₂
(initial concentration × initial volume = final concentration × final volume)

C1> C2, V1<V2

Question 4

Q10: If you dilute 100 mL of 2 M solution to 500 mL, what’s the new concentration?

Answer 4

c₂ = (c₁V₁) / V₂ = (2 × 100) / 500 = 0.4 M

Question 5

Glasswares

Answer 5

Pipette, Volumetric flask,scoopula

Question 6

Concentration units

Answer 6

[ mol dm -3 ] or [gdm -3]

mol/L or M

Question 7

Concentration formula

Answer 7

C = n/v

Question 8

Convert cm3 to dm3

Answer 8

1dm3 = 1000 cm3

Question 9

Define stock solution

Answer 9

the original solution that you prepare

Question 10

What is a volumetric flask

Answer 10

Specially callibrated tool for making a precise volume of solution (cm3/ml)

Question 11

How to determine the mass of solute needed

Answer 11

C x V x Mr(of the solute)

Question 12

Define solutes

Answer 12

The substance that gets dissolved in the solvent, generally present in the lesser amount

Question 13

Define solvent

Answer 13

The substance that does the dissolving, generally present in the greater amount

Question 14

Why is the concentration of a solution expressed per final volume, not per volume of solvent added

Answer 14

Solute occupies the empty spaced b/w H2O molecules when dissolved, increasing the volume

Question 15

L to dm3

Answer 15

1L = 1dm3

Question 16

Explain why chemical compounds tend to dissolve more quickly in hot solvent than in cold solvent.