Fundamentals of Chemistry | Chapter # 1 | Chemistry Class 9th

Science; The knowledge that provides understanding of this world and how it
works is called science.
Q: 01: Define Chemistry.
Ans: The branch of science which deals with composition, structure, properties and reactions of matter is called chemistry. The useful aspects of chemistry are following:-
(i) Petrochemical products. (ii) Soap and detergents.
(iii) Medicines and drugs. (iv) Papers and plastics.
Q: 02: Write the names of branches of Chemistry.
Ans: (i) Physical Chemistry (ii)Organic Chemistry (iii)In-organic Chemistry (iv)Bio-Chemistry (v)Industrial Chemistry (vi) Nuclear Chemistry
(vii) Environmental Chemistry (viii) Analytical Chemistry.
Q: 03: What is Physical Chemistry?
Ans: The branch of chemistry that deals with physical properties of matter and its composition is called physical chemistry.
For example: To determine melting and boiling point, study the effect of temperature or radiation on matter.
Q: 04: Define Organic Chemistry.
Ans: The branch of chemistry that deals with study of hydrocarbons and their derivates is called organic chemistry. Example: Study of petroleum and its products.
Q: 05: Define In-organic Chemistry.
Ans: The branch of chemistry that deals with study of all elements and their compounds except hydrocarbons compounds is called in-organic chemistry. Example: The study of soap, glass, cement etc.
Q: 06: Define Bio-Chemistry.
Ans: The branch of chemistry that deals with study of structure, composition, and chemical reactions in living organisms is called bio-chemistry.
Example: Study of photosynthesis and respiration in living things. Similarly the effect of medicine and food are discussed in this branch of chemistry.
Q 07: Define Industrial Chemistry?
Ans: The branch of chemistry that deals with the manufacturing of chemical compounds on commercial scale is called industrial chemistry.
Example: The Study of manufacturing of industrial products such as sugar, paints and soap etc.
Q: 08: Define Nuclear Chemistry?
Ans: The branch of chemistry that deals with properties of radioactivity and nuclear reactions is called nuclear chemistry.
Example: The preservation of food and generation of electrical power through nuclear reactor are discussed in this branch of chemistry.

Q: 09: Define Analytical Chemistry.
Ans: The branch of chemistry that deals with analysis of a sample to identify its components is called analytical chemistry.
Example: Determination of nitrogen in urea and clinical analysis of blood etc.
Q: 10: Define Environmental Chemistry.
Ans: The branch of chemistry that deals with study of environmental components and the effects of human activities on the environment is called environmental chemistry.
Example: Study of industrial pollution and its effects on ecosystem.
Q: 11: What is Matter?
Ans: Anything that has mass and occupies space is called matter.
Example: Our body and all things around us. It has three physical states
(i) Solid (wood, stone) (ii) Liquid (water, milk) (iii) Gas (air, oxygen, CNG)
Q: 12: Define Substance.
Ans: Piece of matter in pure form is called substance. Every substance has fixed composition and properties. It cannot be divided in to small pieces by physical methods. For example; Water, Carbon.
Q: 13: What are the physical properties?
Ans: The properties that are associated with physical state of a matter are called physical properties. For example; Color, smell, melting point, boiling point.
When ice is heated it melts to water and water is further heated it boils to steam. In this process physical state of water changes but chemical composition remain the same.
Q: 14: What are Chemical properties?
Ans: The properties which are associated with chemical composition of matter are called chemical properties. For example; rusting of iron, decomposition of
water. 2H2O 2H2 + O2

[saifullahbrohi]

I am also chemistry teacher, u have best explained topic dear.

[abdullahumer]

Sir your method of teaching is super excellent kindly upload all the lessons lectures of chemistry 9 to 12.lot of prayer and wishes for u and ur family

[raheelsarwar]

Thankyou so much Sir. Your lecture helped my daughter alot in understaning about chemistry. Her concepts are very much clear now. Allah Apko bht kamyab kary Ameen❤

[ahadsafdarku]

God bless you bhai
My son was doing 9 class chemistry n Maths with you both of his papers gone excellent mashalla
I am extremly thankful to bhai

[amirwaseem]

You are so genius teacher sir ji.Your teaching style is so cool.May you live long. Ameen

[PariKiParwaaz]

Excellent teaching....Liked Ur way of teaching.Sir u have cleared all doubts about chemistry

[imranchoudhary]

GREAT GREAT GREAT LECTURE YOU DELIVERED SIR...
Really APPRECIATE YOU.
ALLAH BLESS YOU.
KEEP IT UP.

[Godieinaditch]

Amazing lecture sir 😄. U made me understand everything I was confused about 😃. Thank you 💕

[iamalreadybroken]

Sir thanks for teaching us Allah give you all hipness

[humrazkhannew]

Sir ap kitny talented hai 😮Kash me bhi hoti 😥

[mona-xzod]

i have my chemistry test in the morning (its 2am rn) please pray it goes well i feel very anxious :( thankfuly these lectures r here 2 help me thank u for explaining it so well :)

[raoaqibjaved]

Mashallah Yar sir Allah ap ko is ka ajar zror Dy ga ap students ko free me classes Dy rahy hain wrna AJ Kal kon free classes deta hai sb fees k pichy Hain Allah ap ko is ka ajar Dy ga inshallah

[SabaRani-gzmp]

Kon kon khta hai k chemistry difficult hai, me b khti joon k chemistry is very difficult, deeply and boring, hmm

[mirshad]

*My name is Memoona I am very impressed your lectures.*

[qilljgj]

Thanks 😊 Sir your lectures is very good for me thanks 😊 Sir

[hinaliaqat]

so nice teaching and example this lecture is so help full for me thank you sir👍👌🧠

[khanbalouch]

Plz apni sary lectures bhejty rhiye ga mashallah boht acha apny bachun I liye intazam kiya allah apko kuch rkhy

[priyanain]

Sir thank you very much 😊 it is very helpful to you

[zonimughal]

Assalamualaikum respected sir mainy 12 sal bad study start ki hai or matric with computer science kar rahi hon apky lectures Meri boht help kar rhy Hain JazakaAllah ❤️

[PRO_GAMER]

You are the best teacher 🙂 very good explanation 😉