C5

Question 1

What is concentration

Answer 1

The amount of substance (solute) dissolved in a certain volume of the solution

Question 2

What is the equation for amount in moles

Answer 2

Amount in moles = concentration x volume

Question 3

What is the equation for mass

Answer 3

Mass = concentration x volume

Question 4

What is the process to get a standard solution

Answer 4

1) weigh out a specific amount of solute.
2) add a small amount of the solvent.
3) swirl mixture until dissolved.
4) add more solvent until reach mark on the volumetric flask

Question 5

How do you convert from cm3 to dm3

Answer 5

Divide cm3 by 1000, so 1dm3 = 1000cm3

Question 6

what 4 ways can we use to measure gas

Answer 6

inverted measuring cylinder. burette. gas syringe. pan-top-balance-mass loss

Question 7

what is the molar volume

Answer 7

1 mole of any gas occupies a volume of dm3 at room temperature and pressure

Question 8

what is the equation for number of moles (dm3)

Answer 8

number of moles = volume (dm3) ÷ 24

Question 9

what is the equation for number of moles (cm3)

Answer 9

number of moles = volume (cm3) ÷ 24000

Question 10

what is the equation for theoretical yield

Answer 10

theoretical yield = (mass of reactant ÷ RFM of reactant) x RFM of product

Question 11

what is the equation of percentage yield

Answer 11

percentage yield = (actual yield ÷ theoretical yield) x 100

Question 12

What is the equation for atom economy

Answer 12

Atom economy = mass of wanted products (x100) ÷ total mass of products

Question 13

What is the equation for rate of reaction

Answer 13

Amount of produce formed/time taken

Question 14

how can we measure rate of reaction

Answer 14

take samples for titration, measure mass lost on a balance, measure volume of gas evolved, temperature change, colour changes

Question 15

what factors affect the rate of reaction

Answer 15

temperature, concentration, pressure, catalysts and surface area

Question 16

what is rate of reaction

Answer 16

rate of reaction is how much of the reaction occurs per unit of time

Question 17

what do we measure rate of reaction in

Answer 17

g/s or g/min. cm³/s or cm³/min. 1/s or 1/min (for a colour change reaction)

Question 18

what is the volume of one mole of gas

Answer 18

one moles of any gas has a volume of 24dm³ at room temperature and pressure

Question 19

what is the equation for number of moles of a gas

Answer 19

number of moles of a gas = volume of a gas ÷ 24dm³

Question 20

how does a titration work

Answer 20

1) known volume of alkali must be measured. 2) acid added gradually, swirling to mix, until indicator shows a neutral solution. 3) first attempt gives approximate value. 4) repeat at lease 3 times discarding anomalies or results where the solution goes ‘past’ neutral