Acids, Bases & Salts

Question 1

what is the chemical formula for ethanoic acid ?

Answer 1

CH3COOH

Question 2

what is the chemical formula for phosphoric acid ?

Answer 2

H3PO4

Question 3

what is the formula for a phosphate ion ?

Answer 3

PO4 - 3

can be PO3 - 4

Question 4

give the definition for an acid

Answer 4

a substance that releases H+ ions in aqueous solution (it is a proton donor)

Question 5

what are the differences between a strong / weak acid ?

Answer 5

• strong acid fully dissociates in solution / weak acid partially dissociates in solution
• weak acid dissociation is reversible, strong acid isn’t

Question 6

what types of acids are usually weak ?

Answer 6

carboxylic / organic acids that have a similar structure to ethanoic acid

Question 7

what happens when ethanoic acid is placed in solution ?

Answer 7

partially dissociates into H+ and CH3COO- ions

Question 8

what type of acid is usually strong ?

Answer 8

mineral acids

Question 9

how can an acid be notated ?

Answer 9

HA

Question 10

what is a base ?

Answer 10

a proton acceptor

Question 11

what happens between water soluble oxides and water ?

Answer 11

they form aqueous hydroxides

Question 12

what is the formula of a hydronium ion ?

Answer 12

H3O+

Question 13

how is a hydronium ion formed ?

Answer 13

When an acid dissociates in water, the H+ ion is accepted by a water
(this is an example of water acting as a base)

Question 14

give the definition of an alkali

Answer 14

a soluble base that releases OH- ions in water

Question 15

what are the 3 most common alkalis ?

Answer 15

NaOH / KOH / NH3

Question 16

give the definition of a salt

Answer 16

ionic compounds formed when H+ ions in acids are replaced by metal / ammonium ions

Question 17

what is the charge of lead and zinc usually ?

Answer 17

2+

Question 18

when stating observation of solid what must you state ?

Answer 18

the colour of the solid

Question 19

acid + metal hydrogen carbonate =

Answer 19

salt + water + carbon dioxide

Question 20

When silver halides are exposed to light, they decompose to release silver metal. What is this used for ?

Answer 20

photography

Question 21

what is the test for sulfate ions ?

Answer 21

add HCl, then barium chloride to sample

will form a white precipitate of barium sulfate

Question 22

what is the flame test colour of barium ?

Answer 22

pale green

Question 23

what is the flame test colour of calcium ?

Answer 23

yellow - red

Question 24

what is the flame test colour of copper ?

Answer 24

green - blue

Question 25

what is the flame test colour of lithium ?

Answer 25

red

Question 26

what is the flame test colour of sodium ?

Answer 26

orange

Question 27

what is the flame test colour of potassium ?

Answer 27

lilac

Question 28

what is the colour of copper (||) + NaOH ?

Answer 28

light blue precipitate

Question 29

what is the colour of iron (||) + NaOH ?

Answer 29

green precipitate

Question 30

what is the colour of copper (||) alone ?

Answer 30

blue

Question 31

what is the colour of Iron (|||) + NaOH ?

Answer 31

red - brown precipitate

Question 32

what is the test for ammonium ions ?

Answer 32

Add aqueous sodium hydroxide to sample and warm mixture. Result should be smell of ammonia and damp red litmus turning blue (alkali)

Question 33

what is the test for halides ?

Answer 33

add nitric acid, followed by silver nitrate | will form a silver precipitate

Question 34

what is the product of ammonia + acid ?

Answer 34

ammonium salt

Question 35

in titration, where should you read value from ?

Answer 35

bottom of meniscus

Question 36

state color of methyl orange in acid

Answer 36

red

Question 37

state color of methyl orange in alkali

Answer 37

yellow

Question 38

state color of phenolphthalein in acid

Answer 38

colourless

Question 39

state color of phenolphthalein in alkali

Answer 39

pink

Question 40

what is an analyte ?

Answer 40

unknown solution with unknown conc that you are finding

Question 41

(simple) how is standard solution made ?

Answer 41

dissolving known amount of solid in known amount of water

Question 42

what is a polyprotic acid ?

Answer 42

acid that donates more than one proton