Acids and bases

Question 1

Arrhenius’s theory of Acids

Answer 1

Compounds that ionise in water to form H+ ions (molecular compound that forms ions)

Question 2

What is a strong acid

Answer 2

Acid that dissociates and releases all of its hydrogen ions (single arrow)

Question 3

What is a weak acid

Answer 3

Acid that only partially releases hydrogen ions (double arrow)

Question 4

Examples of strong acids

Answer 4

H2SO4, HBr, HI, HNO3, HClO4, HCL

Question 5

Types of acids

Answer 5

polyprotic, monoprotic, diprotic, triprotic

Question 6

Polyprotic

Answer 6

Describes any acid that is capable of donating more than 1 proton

Question 7

Monoprotic

Answer 7

Donate 1 proton

Question 8

Diprotic

Answer 8

Donate 2 protons

Question 9

Triprotic

Answer 9

donate 3 protons

Question 10

Arrhenius theory of bases

Answer 10

Compounds that dissociate in water (forms hydroxide ions)

Question 11

What is a bases strength dependent on

Answer 11

Dependent on the concentration of ions in solution and ability to accept hydrogen ions (protons) from an acid

Question 12

describe a strong base

Answer 12

Releases hydroxide ions in solution, don’t accept protons easily

Question 13

Weak base

Answer 13

partially ionise into hydroxide ions in solution

Question 14

Example of strong bases

Answer 14

All group 1 and 2 SOLUBLE hydroxides, Ca(OH)2 and Mg(OH)2 even though they have low solubility

Question 15

Properties of acids

Answer 15

Turn litmus paper from blue —> red, electrical conductors, pH of less than 7, sour, corrosive

Question 16

Properties of bases

Answer 16

Turn litmus paper from red —> blue, electrical conductors, pH of more than 7, bitter, caustic and slippery

Question 17

pH scale

Answer 17

Measure of the amount of alkalinity or acidity in solution, Measure of the amount of protons (hydrogen ions) that are present in an aqueous solution

Question 18

How does the pH scale work

Answer 18

less than 7- acidic
7 or 8- neutral
9 or more- basic

Question 19

Indicators

Answer 19

weak acid or base that change colour based on the pH of a substance

Question 20

Universal indicator

Answer 20

mixture of several indicators, displays a variety of colours over the pH scale (allows a range of 1-14)

Question 21

Electrolytes

Answer 21

ions in a solution

Question 22

Dissociation

Answer 22

producing ions in a solution (ionic solids where the ions already present are separated)

Question 23

Ionisation

Answer 23

covalent substances where the solid reacts to form ions

Question 24

Strong electrolytes

Answer 24

Exist completely as ions when dissolved in solution, High electrical conductivity in solution, All soluble ionic compounds (HCl, H2SO4, HNO3, AgCl, Mg(OH)2)

Question 25

Weak electrolytes

Answer 25

Only a small proportion of molecules will ionise in solution

Question 26

Non-electrolytes

Answer 26

Most covalent molecular substances such as sugar and ethanol that don’t produce ions when dissolved in solution, Low electrical conductivity

Question 27

Bronsted-Lowry theory of acids

Answer 27

Species that donates a proton (H+)

Question 28

Bronsted-Lowry theory of bases

Answer 28

Species that accepts a proton (H+)

Question 29

Arrhenius’s theory limitations

Answer 29

doesn’t explain why some substances that don’t contain hydrogen still create an acidic solution when added to water (e.g. CO2 + water= acidic, NH3 + water= basic), restricted to acids and bases that dissolve in water and doesn’t explain acid-base behaviour in non-aqueous solutions

Question 30

Electrolyte

Answer 30

substance that produces electrically conduction solutions when dissolved in water

Question 31

Is water a strong or weak electrolyte

Answer 31

Weak electrolyte as only a small number of ions is produced

Question 32

Kw=

Answer 32

(H+)(OH-)/1, =10^-14 at 25 degrees c