Additional notes

Question 1

Water can act as both an acid and a base making it

Answer 1

amphoteric

Question 2

If the number of hydrogen that was given was for a base what are you actually solving for

Answer 2

Potential of hydroxide

Question 3

What is considered as weak acid

Answer 3

3-6

Question 4

what is considered as a strong base

Answer 4

11-14

Question 5

What is considered as a strong acid

Answer 5

3 below

Question 6

what is considered as a weak base

Answer 6

8-10

Question 7

Why should water be added first before acids

Answer 7

It will cause an explosion due to exothermic reactions

Question 8

What does weight accurately mean

Answer 8

Using analytical balance

Question 9

Is it necessary to perform titration with blank

Answer 9

yes

Question 10

Common name of barium hydroxide

Answer 10

Baryte

Question 11

what is carbonate error

Answer 11

refers to how reactive OH is to carbon atoms, which may alter the concentration of OH

Question 12

Why polyolefin containers

Answer 12

To prevent leeching

Question 13

Why are the primary standards dried

Answer 13

to remove impurities

Question 14

sonication / water bath

Answer 14

the process done to prevent carbonate error

Question 15

Why does some titration need residual titration

Answer 15

Insoluble
Sharp-end point
Slow
Volatile

Question 16

Importance of filter

Answer 16

separates the intermediates

Question 17

What temperature is Ignition conducted

Answer 17

700 degrees

Question 18

Why should zinc oxide be ignited first

Answer 18

should can react with carbon dioxide to form zinc carbonate

Question 19

Why is ammonium chloride added in assay of Zinc oxide

Answer 19

To separate undissolved components

Question 20

Why should zinc oxide assay need to be gently heated

Answer 20

necessary to increase the rate of reaction between zinc oxide and sulfuric acid

Question 21

Why should boric acid by dried and accurately weighed

Answer 21

To ensure that H3BO3 will be free from moisture and the exact amount of H3BO3 will be used in the assay

Question 22

Why is boric acid dissolved in glycerin

Answer 22

boric acid is a weak acid to be titrated quantitatively in an aqueous solution with an alkali with a visual indicator, however, it can be titrated with a standard alkali in the presence of polyhydric alcohol using phenolphthalein as an indicator. Boric acid is esterified in the presence of polyhydric alcohols such as glycerol or mannitol, forming a monobasic acid that is strong enough to give a satisfactory endpoint (Glycerin makes the boric acid strong so that it may readily react with the titrant NaOH)

Question 23

Why is concentration of sugar alcohol be at least 30%

Answer 23

to prevent complex acid

Question 24

Why is glycerin used in boric acid

Answer 24

forms a slightly dissociated complex with the metaborate ion which prevent the reversal of the reaction

Question 25

Glycerin should be neutralized with 1 N NaOH

Answer 25

Since it imparts acidity to the solution and thus may increase consumption of the VS

Question 26

Aspirin by nature is an ester as such:

Answer 26

it is readily hydrolyzed when come in contact with water

Question 27

What should you use to measure aspirin

Answer 27

weighing bottle, to reduce exposure to air

Question 28

What type of titrant is the 0.5 N sodium hydroxide in Aspirin

Answer 28

excess titrant

Question 29

What type of titrant is the 0.5 N sulfuric acid in Aspirin

Answer 29

Back titrant

Question 30

Importance of blank titration:

Answer 30

for correction of data

Question 31

Why should aspirin be diluted in sodium hydroxide

Answer 31

Since it is a weak acid

Question 32

Residual titration of acidimetry

Answer 32

• Assay of Milk of Magnesia
• Assay of Methenamine
• Assay of Ammonium Chloride Injection
• Assay of Zinc Oxide

Question 33

For nitrogen determination (in organic substances plus the
nitrogen contained in the inorganic compounds ammonia and
ammonium)

Answer 33

Kjeldahl Method

Question 34

Residual Titration for alkalimetry

Answer 34

Assay of Aspirin