10C- calculating pH

Question 1

Define
acidic solution

Answer 1

Solution containing a greater concentration of hydronium ions than hydroxide ions

Question 2

Define
basic solution

Answer 2

Solution containing a greater concentration of hydroxide ions than hydronium ions

Question 3

Define
neutral solution

Answer 3

Solution containing an equal concentration of hydronium and hydroxide ions

Question 4

Define
autoionization

Answer 4

Process by which an atom or molecule spontaneously forms ions

Question 5

Define
ionic product of water (Kw)

Answer 5

Expression of the concentration of ions present in water at 25 °C

Question 6

Define
pH

Answer 6

Measure of the concentration of hydronium ions in a solution

Question 7

Define
pH scale

Answer 7

pH values arranged on a logarithmic scale

Question 8

Ionic(n.) product
definition

Answer 8

-Ionic product(n.)=The product of
concentrations of ionic species

Question 9

Ionisation(v.)
definition

Answer 9

-Ionisation(v.)=Conversion of substance into
ions.

Question 10

Acidity definition

Answer 10

-Acidity(adj.)=level of acid in a substance

Question 11

what happens when water is ionised

Answer 11

H2O(l) + H2O(l) H3O+(aq) + OH−(aq)
water acts as a weak acid and weak base

Question 12

list some monoprotic acids

Answer 12

hydrochloric acid (HCl), ammonium (NH4), nitric acid (HNO3), ethanoic acid (CH3COOH)
HANE (hydrochloric acid, ammonium, nitric acid, ethanoic acid)

Question 13

define monoprotic

Answer 13

species that can only donate one proton, H+, during ionisation

Question 14

list some diprotic acids

Answer 14

sulfuric acid (H2SO4), carbonic acid (H2CO3), hydrogen sulfide (H2S), selenous acid (H2SeO3)
SCHS ( sulfuric acid, carbonic acid, hydrogen sulfide, selenous acid)

Question 15

define diprotic

Answer 15

species that can donate up to two protons, H+, during ionisation

Question 16

list some triprotic acids

Answer 16

phosphoric acid (H3PO4), citric acid (C6H8O7), arsenic acid (H3AsO4), boric acid (H3BO3)
PCAB

Question 17

define triprotic

Answer 17

species that can donate up to three protons, H+, during ionisation

Question 18

list some amphiprotic acids

Answer 18

water (H2O), hydrogen sulfate ( HSO4(-)),hydrogen carbonate (HCO3(-)), di hydrogen phosphate (H2PO4(-)), hydrogen phosphate ( HPO4(2-))

Question 19

define amphiprotic

Answer 19

species that can either donate or accept a proton, H+

Question 20

define pH

Answer 20

measure of the concentration of hydronium ions in a solution

Question 21

kW formula (aka ionic product formula)

Answer 21

Kw = [H3O+] × [OH−]
Kw = (1.00 × 10−7 M) × (1.00 × 10−7 M)
Kw = 1.00 × 10^−14 M2

Question 22

pH formula

Answer 22

pH = −log10[H3O+]

Question 23

what is kW

Answer 23

the ionic product of water: expression of the concentration of ions present in water at 25°C

Kw is always equal to 1.00 ⨉ 10-14 M^2 at 25°C

This formula only valid at 25 degrees Celsius

Question 24

If neutral pH is still defined as when [H3O+] = [OH–], what would be considered neutral pH at 100°C, assumingKwis equal to 51.3 × 10–14M2?

Answer 24

H3O x OH = 51.3 x 10^-14
H3O=OH
H3O x H3O = 51.3 x 10^-14
H3O= √51.3 x 10^-14
H3O= 7.162 x 10^-7
pH= -log 10 (7.16 x 10^-7)
pH=6.14

Question 25

Acid solutions ratio of H3O+ and OH- concentration

Answer 25

pH 7 < [H3O+] >1.0 × 10−7 M and [OH−] < 1.0 × 10−7M

Question 26

Neutral solutions ratio of H3O+ and OH- concentration

Answer 26

pH = 7, [H3O+] = [OH−] = 1.0 × 10−7 M

Question 27

basic solutions ratio of H3O+ and OH- concentration

Answer 27

pH 7 >[H3O+] <1.0 × 10−7 M and [OH−] >1.0 × 10−7M

Question 28

how to calculate pH

Answer 28

pH = −log10[H3O+]

Question 29

how to calculate H3O concentration

Answer 29

[H3O+] = 10^−pH

Question 30

what factor is pH change

Answer 30

every increase or decrease in pH by 1 means that there was a change in the concentration of H3O by a factor of 10

Question 31

Calculate the pH of a 0.30 M solution of hydrochloric acid at 25 .

Answer 31

[HCl] = [H3O+] = 0.30 M
pH = −log10[H3O+]
pH = −log10 (0.30 M)
pH = 0.52

Question 32

Explain the
autoionisation of water.

Answer 32

-Pure water
undergoes a tiny degree of ionisation with itself
-This is possible
due to water’s amphiprotic nature

H2O(l){acid}
+ H2O(l){Base}⇌ H3O^(+)(aq) + OH^(-)

-There will be
very low concentrations of product as only a small amount of this reaction
will occur due to the strenght of the acid and base being low.

Question 33

What does pH stand
for(not necessary but fun)

Answer 33

What
does pH stand for?=Potenz of hydrogen=power of hydrogen=
-p=power=originates
from the german word potenz
-H=hydrogen

Question 34

What is the pH
scales and what does it do

Answer 34

-measurement of
acidity= simplified further using measurement of pH
-pH scale=
measurement of acidity of a solution on a scale of 0-14(this only valid at 25 degrees Celsius )