Unit: 2-How do chemical reactions shape the natural world?

Question 1

calculation of concentration (M=molarity)

Answer 1

C=n(amount of moles) / V (volume/litres/L) [1000mL=1L]

Question 2

if want to know n(mole) using concentration and volume

Answer 2

n=CxV

Question 3

if we want to know the pH of the solution and want to work out the concentration of [H3O+] acid

Answer 3

[H3O+] =10^-pH
[H3O+] =10^-2
=0.01M

Question 4

if we want to know the pH of the solution and want to work out the concentration of [OH-] base

Answer 4

example:
[H3O+] =pH=2
[H3O+] =10^-2=0.01M
step2:
[OH-]=10^-14/[H3O+]
[OH-]=10^-14/10^-2
=10^12

Question 5

when determining the pH and a solution is diprotic or produces two OH- ions you…

Answer 5

times the molarity by two at the beginning

Question 6

when determining the concentration and a solution is diprotic or produces two OH- ions you…

Answer 6

you divide by two at the end

Question 7

from mL to L

Answer 7

/1000

Question 8

formula dilutions

Answer 8

M1V1= M2V2
rearrange

Question 9

what are amphiprotic substances?

Answer 9

substances that can act as an acid or a base

Question 10

common acids

Answer 10

hydrochloric acid(HCl)
sulfuric acid H2SO4
Nitric acid HNO3
Phosphoric acid H3PO4
ethanoic acid CH3COOH
carbonic acid H2CO3

Question 11

common bases

Answer 11

Sodium Hydroxide NaOH
Ammonia NH3
Calcium Hydroxide Ca(OH)2
Magnesium Hydroxide Mg(OH)2

Question 12

strong Vs weak

Answer 12

ability to donate or accept protons
one arrow=strong
two arrows=weak

Question 13

strong dilute=

Answer 13

broken down/ionised (ex. HCl will be in bits of H and Cl)
however little solution/ substance

Question 14

strong concentrated

Answer 14

broken down/ionised (ex. HCl will be in bits of H and Cl)
A lot of solution/ substance

Question 15

weak concentrated

Answer 15

little bit broken down/ionised
A lot of solution/ substance

Question 16

waek dilute

Answer 16

nothing broken down
little solution/ substance