biochem POST LAB TEST

Question 1

The liquid that passes through the filter paper during filtration

Answer 1

filtrate

Question 2

The filtration method is not suitable for separating soluble solids from a liquid.

Answer 2

True

Question 3

The eye is kept at the 1________ meniscus to get the volume of a colorless solution and at the 2_______ meniscus to know the volume of a colored solution.

Answer 3

1 lower, 2 upper

Question 4

The gas used in the lab as a source of fuel is ______ gas.

Answer 4

butane

Question 5

Adjusting the ________ of the Bunsen burner changes the height of the flame.

Answer 5

gas valve

Question 6

When using the Bunsen burner for heating, the flame should be a ________ flame.

Answer 6

None Luminous

Question 7

_______ Heating is a safer way of heating non-flammable liquids than a water bath or a steam bath.

Answer 7

Direct

Question 8

It is proper to inspect the rubber tubing attached to the Bunsen burner for cracks or any other defects

Answer 8

True

Question 9

Paper may be used to transfer solid substances to a small-mouthed container.

Answer 9

True

Question 10

The _______ of the Bunsen burner is adjusted to regulate the flow of the air and to produce the desired color or nature of the flame.

Answer 10

Colar

Question 11

The solid product that remains on the dish after evaporation is called ________.

Answer 11

Residue

Question 12

__________ is a basic purification method used in the laboratory that relies on a porous material and gravity.

Answer 12

Decantation

Question 13

Before transferring solid chemicals, the container to be used must be clean and damp to avoid contamination.

Answer 13

False

Question 14

A solid substance formed during a chemical reaction is called the _________.

Answer 14

precipitate

Question 15

It is necessary to cover the test tube with a cork when heating solutions over direct flame.

Answer 15

False

Question 16

The solid substance that remains on the filter paper after filtration is called _______.

Answer 16

Residue

Question 17

The Bunsen burner to be used must be placed near the combustible materials and chemicals.

Answer 17

False

Question 18

A clean and dry spatula can be used to spoon out the solid chemicals from its container.

Answer 18

True

Question 19

The proper way to light a Bunsen burner is to slowly open the gas valve and then bring a lighted match near the tip of the burner.

Answer 19

True

Question 20

Test for Unsaturation

Answer 20

Von Bayers Test and Bromine Test

Question 21

Alkanes are _______, Compared to the other 2

Answer 21

Saturated

Question 22

Alkanes and Alkynes are __________

Answer 22

Unsaturated

Question 23

_______ Contains carbon-carbon double bond but is not considered unsaturated

Answer 23

Benzene ring

Question 24

Von Bayers test:
Uses __________ __________ or (______) to oxidize alkenes and alkynes

Answer 24

Potassium Permanganate (KMnO4)

Question 25

Von Bayers test:
Product -

Answer 25

Manganese Dioxide (MnO2)
Removes violet color and makes it brown positive for unsaturation

Question 26

Bromine Test:
_________ is added to alkenes and alkynes

Answer 26

Bromine

Question 27

Bromine Test:
Product - _______________ and ________________

Answer 27

Dibromoalkanes and Tetrabromoalkanes
if it disappears, then it is positive for unsaturation

Question 28

Test for alcohols and phenols

Answer 28

Finds Hydroxyl groups -
Boardwell - wellmans test

Labels Hydroxyl groups into 1,2,3* -
Lucas test

Specified to detect phenols -
Ferric chloride

Question 29

Boardwell - wellmans test:
Uses __________ _________ or (________) Dissolved in ________ _______ That makes ___________ ___________ or (_____)

Answer 29

Potassium dichromate (KR2CR2O2) +
Sulfuric acid = Hexavalent Chromium or (CR6+)

Question 30

Boardwell - wellmans test:
1* and 2* oxidizes into 1_________ _____ and 2_________ respectively
this is the product CR6+ Becomes 3________ ____ OR (_____)

Answer 30

1- carboxylic acid, and 2- ketones, 3- Chromic Ions, (CR3+)
Green color

Question 31

Boardwell - wellmans test:
Phenols will produce _____________

Answer 31

benzoquinone
brown color

Question 32

Boardwell - wellmans test:
What will happen to 3* or tertiary alcohols

Answer 32

Nothing lol. They’re not affected

Question 33

Lucas Test:
Uses 1__________ _________ ______ and 2______ _________

Answer 33

1- Concentrated Hydrochloride acid, 2- Zinc chloride

Question 34

Lucas Test:
Converts 1, 2, 3* Into ______ ______

Answer 34

alkyl groups
emulsion = positive

Question 35

Lucas Test:
From 1* to 3* the reaction becomes more _______

Answer 35

Rapid

Question 36

Ferric Chloride test:
(_____) or___ _______ ________ solution is needed on phenols

Answer 36

(Fe3+) or 2% Ferric Chloride solution

Question 37

Ferric chloride:
The product is a color change from Orange to ______

Answer 37

Violet

Question 38

Test for aldehydes and Ketones

Answer 38

2,4 DNP Test
Tollens Test

Question 39

2,4 DNP Test:
1_______ Carbonyl groups (aldehydes and ketones) by adding 2_____________________

Answer 39

1- Detects, 2- Dinitrophenylhydrozine

Question 40

2,4 DNP Test:
If , _____________________ is found, it tests positive for both ketones and aldehydes. Becomes a yellow or orange-red precipitate.

Answer 40

2,4 Dinitrophenylhydrozone

Question 41

Tollens test:
__________ aldehydes and ketones,

Answer 41

distinguishes

Question 42

Tollens test:
Based on that, aldehydes can _________, and ketones cannot

Answer 42

oxidize

Question 43

Tollens test:
______ _________ ________ or ___(____)___ is added to a substance

Answer 43

Silver Ammonia Complex OR Ag(NH3)2+

Question 44

Tollens test:
Silver ion is reduced to ________ ______

Answer 44

elemental silver

Silver mirror = positive test = aldehydes

Question 45

Test for Carboxylic acids

Answer 45

Sodium Bicarbonate test

Question 46

Sodium Bicarbonate test:
1______ _________is produced in the presence of 2___________.

Answer 46

1- Carbon dioxide, 2- effervescence

effervescence = Positive test

Question 46

Sodium Bicarbonate test:
________ ________ _________ is added to the test tubes

Answer 46

Sodium bicarbonate Solution