Amount Of Substance

Question 1

What unit can amount of substance be measured by

Answer 1

Mol

Question 2

How many particles does one mole contain

Answer 2

6.02 x 10^23

Question 3

What is the name given to this specific number of particles

Answer 3

Avogadros constant

Question 4

Does the n.o of particles in one mole change dep on what the substance is

Answer 4

No it doesn’t change for atoms, molecules, electrons, ions etc

Question 5

Fill in the gap
1 mole of any substance contains

Answer 5

6.02 x 10^23 atoms, ions, electrons, molecule
Eg one mol of sodium ions contains 6.02 x 10^23 ions

Question 6

Eq for number of particles

Answer 6

N.o of particles (atoms, molecules, ions etc) = n.o of mol x avogadros constant

Question 7

Finish the sentence
1 mol of any substance has a mass …

Answer 7

That’s the same as it’s relative molecular mass (Mr) in grams

Question 8

Equation for n.o of moles

Answer 8

Mass
————
Mr

Question 9

Eq and units for conc

Answer 9

Conc = mol / mass
———————
Vol
Conc = mol dm^-3
Vol = dm3

Question 10

How many cm3 in 1dm3

Answer 10

1000cm3 = 1dm3

Question 11

Ideal gas equation and units

Answer 11

Pv = nRT
P = pressure = pascals
V = volume = m3
R = gas constant = J mol ^-1 K-1
T = temperature = K/•c

Question 12

Vol of one mol of any gas

Answer 12

One mol of any gas has a vol of 24dm3 at room temp and pressure

Question 13

What is room temp and pressure

Answer 13

20 degrees Celsius
101,000 pa

Question 14

Mol equation using vol

Answer 14

V
N = ——
24

Question 15

How many dm3 in m3

Answer 15

1000dm3 = 1m3
Divide by 1000

Question 16

How many cm3 in 1 m3

Answer 16

1,000,000 cm3 = 1m3
Divide by 1,000,000

Question 17

What is ideal gas constant

Answer 17

8.314 J mol -1 K -1

Question 18

How to convert from degrees Celsius to kelvin

Answer 18

Degrees celcius ——> kelvin
+ 273

Question 19

From kelvin to degrees Celcius

Answer 19

K ——> celcius
-273

Question 20

4 assumptions for ideal gas

Answer 20

1) gas molecules r tiny compared to spaces bet them
2) no forces acting bet gas mol
3) gas mol move randomly
4) collisions bet gas mol are elastic

Question 21

What do ionic equations only show

Answer 21

Reacting particles

Question 22

Steps of writing ionic equation

Answer 22

1) write full balanced equation
2) rewrite equation into its ions
3) cross out spectator ions on both sides of reaction

Question 23

What cannot be broken down into ions

Answer 23

Gases and solids

Question 24

Phenolphthalein colour changes

Answer 24

Pink in alkali
Colourless in acid

Question 25

Methyl orange

Answer 25

Yellow in acid
Red in alkali

Question 26

Equation for percentage yield

Answer 26

Percentage yield = actual yield
——————. X 100
Theorifcal yield

Question 27

Atom economy

Answer 27

Mass if desired prod
—- —————————
Mass of total prod

Question 28

Benefits of high atom economy

Answer 28

• less waste w high atom economy so helps environment
• raw materials used more efficiently so increased sustainability
• less by products and less time and money separating them from desired product