Chem

Question 1

Define acid.

Answer 1

sour in nature
Produce H+ ions(cations)
Eg of strong acids is:H2so4,Hno3,Hcl,h2co3(carbonic acid)

Question 2

What is a base?

Answer 2

bitter/soapy in nature
produce hydroxide ions (OH-)(anions)
strong acids:NAOH(caustic soda),KOH(caustic pottash)

Question 3

reaction of non-metallic oxides with bases

Answer 3

base + non-metallic oxides - salt + H2O
CAOH2 + CO2 - CACO3 + H2O
CO2 is an acidic oxide. Therefore, it is acidic in nature because they give us salt and H2 gas, which is the same as in the neutralisation reaction.

Question 4

indicators and its types

Answer 4

1. natural
   turmeric,litmus,red cabbage
2. Manmade
   phenolphethelin,Mythel orange
   3 . oltactory
   onion,vanilla essencecolve oil

Acids typically taste sour, while bases taste bitter.

Question 5

What is the pH scale used for?

Answer 5

To measure the acidity or alkalinity of a solution.

Question 6

Define salt in chemistry.

Answer 6

A compound formed from the reaction of an acid and a base.

Question 7

What is the pH range of acids?

Answer 7

0 to 7 on the pH scale.

Question 8

What is the pH range of bases?

Answer 8

7 to 14 on the pH scale.

Question 9

How do acids and bases react with metals?

Answer 9

Acid + metals - salt + hydrogen
H2 SO4 + zinc - ZNHo4 + H2
base + metal - salt+ hydrogen
2NAOH + zinc - NA2ZNO2 + H2

Question 10

Reaction of metal carbonates with acids

Answer 10

Metal carbonate/hydrogen carbonates + acid - salt + water +carbon dioxide
CA(OH)2 + CO2 - CACO3 + H2O
CACO3 gives a white precipitate
NA2CO3 + 2HCL - 2NACL + H2O + CO2
NAHCO3 + 2HCL - NACL + H2O + CO3

Bases can feel slippery due to their ability to react with fats and oils.

Question 11

What is an example of a strong acid?

Answer 11

Hydrochloric acid (HCl).

Question 12

What is an example of a strong base?

Answer 12

Sodium hydroxide (NaOH).

Question 13

Fill in the blank: Acids react with metals to produce ______.

Answer 13

Hydrogen gas

Question 14

Define alkali.

Answer 14

A base that is soluble in water.

Question 15

What is the neutralization reaction equation?

Answer 15

Acid + Base → Salt + Water.

Question 16

Fill in the blank: Sodium chloride is a common table ______.

Answer 16

Salt

Question 17

Tooth decay

Answer 17

occurs when the pH of the mouth is lower than 5.5?
Toothpaste are generally basic, so therefore cleaning the teeth neutralise the acid and prevents to decay

Acids ionize in solution, allowing them to conduct electricity.

Question 18

PH in our digestive system?

Answer 18

stomach produces hydrochloric acid which helps in the digest digestion of food without harming the stomach
During digestion, the body produces too much acid, which causes pain and meditation
To get rid of the pain antacids are used
Milk of magnesia

Question 19

What is the effect of diluting an acid?

Answer 19

It decreases the concentration of H+ ions.

Question 20

Fill in the blank: Vinegar is a dilute solution of ______ acid.

Answer 20

Acetic

Question 21

pH of our body and rain?

Answer 21

7.02 - 7.8?
When Rain is less than 5.6.
It is called acidRain motor is less than 56. It is called acid train

Question 22

Define corrosive.

Answer 22

A property of substances that can damage or destroy living tissue.

Question 23

What is the role of indicators?

Answer 23

To show the presence of acids or bases by changing color.

Question 24

Fill in the blank: Ammonia is a common household ______.

Answer 24

Base

Question 25

True or false: **Acids** turn blue litmus paper red.

Answer 25

TRUE

Question 26

What is the result of mixing an **acid** with a **carbonate**?

Answer 26

Carbon dioxide gas is produced.

Question 27

Define **neutralization**.

Answer 27

The process of reacting an acid with a base to form salt and water.

Question 28

What is the chemical formula for **sulfuric acid**?

Answer 28

H2SO4.

Question 29

Fill in the blank: **Calcium carbonate** reacts with acids to produce ______.

Answer 29

Carbon dioxide

Question 30

What is a **weak acid**?

Answer 30

An acid that partially ionizes in solution, like acetic acid.

Question 31

how is Gypson formed?

Answer 31

CSO4. 1/2H2O(plaster of Paris) + 1 1/2H2O - CASO4.2 H2O (gypsum)

Question 32

What is the chemical formula for plaster of Paris?

Answer 32

CASO4.1/2 H2O or calcium sulphate hemihydrate

Question 33

cloralkali process

Answer 33

when electricity is passed through an aqua solution of sodium chloride decomposes to form sodium hydroxide, this process is known as the chloralkali process because products for a chlorine and alkali for sodium hydroxide 2NACL +2 H2O - 2NAOH + CL2 + H2

Question 34

What is the main component of **baking soda**?

Answer 34

Sodium bicarbonate (NaHCO3). this is a mild noncorrosive basic salt

Question 35

Define **alkaline**.

Answer 35

Having a pH greater than 7; a property of bases.

Question 36

how is baking soda formed?

Answer 36

baking soda is produced by using sodium chloride as one of its NACL +H2O + CO2 + NH3 - NH 4CL(ammonium chloride) + NH CO3 (sodium hydrogen carbonate) when sodium hydrogen carbonate is heated, 2NaHCO3 - NA2CO3 + H2O +CO2 is formed

Question 37

what is water crystallisation?

Answer 37

The fixed number of water molecules present in one formula unit of salt Examples : CUSO4.5 H2O NA2CO3.10 H2O or washing soda

Question 38

What is the primary use of **sodium bicarbonate**?

Answer 38

As a baking agent and antacid.

Question 39

what are the uses of baking soda NAHCO3?

Answer 39

baking soda is used for making baking powder, which is a mixture of baking soda and a mild edible acid Reaction is NAHCO3 + H (ANY ACID) - CO2 + H2O + sodium salt of acid it is used as an ingredient in antacids because it neutralise excess acid in the stomach. It is also used in acid fire extinguishers

Question 40

What is a **strong base**?

Answer 40

A base that completely dissociates in solution, like sodium hydroxide.

Question 41

uses of NAOH sodium hydroxide

Answer 41

chlorine gas forms at the anode the hydrogen gas forms at cathode It is used in water treatment , for decreasing metals, soaps detergent, making an artificial fibres

Question 42

The uses of washing soda

Answer 42

used glass soap and paper industries Manufacture of sodium compound, such as borax Cleaning agent For removing permanent hardness of water

Question 43

Define **pH indicator**.

Answer 43

A substance that changes color at a specific pH level.

Question 44

What is the chemical formula for **acetic acid**?

Answer 44

CH3COOH.

Question 45

Fill in the blank: **Lemon juice** is an example of a ______ acid.

Answer 45

Weak

Question 46

bleaching powder and its uses

Answer 46

CAOCL2 CA(OH)2 + CL2 - CAOCL2 + H20 bleaching , wood pulp in paper, factories, washing clothes, laundry, oxidising agent in many chemical industries to make drinking water, free from germs

Question 47

What is the primary component of **table salt**?

Answer 47

Sodium chloride (NaCl).

Question 48

Fill in the blank: **Baking soda** is a common ______.

Answer 48

Base

Question 49

washing soda

Answer 49

obtained from sodium chloride NA2CO3.10 H2O It is a basic salt re-crystallisation of sodium carbonate gives us washing soda