Mixture || Science Guide

MIXTURE

1. Define Matter:

= Anythings that has mass, and occupied space is called Matter. Actually, there are 3 states of matter: solid, liquid and Gas.

2. Melting point:

→ The temperature at which solid changes into liquid is called Melting Point.

3. Boiling point:

= The temperature at which liquid changes into gas is called Boiling Point.

4. Change in state of matter:

i. Physical change:

→ The temperatery change in which no new no new substance is termed is called physical change eg Melting ice into water, Tearing of paper, etc.

ii. Chemical change:

→ Chemical change is a permanent change in which. a new substance with entirely new properties is produced ag cooking at rice Rusting at iron, etc.

6. Mixture:

= The Permanent substances formed by placing two or more substance together in any proportion by weight is called Mixture eg air, tea, salt solution, etc.

7. Element:

= The simplest pure substances which is made of similar kinds of atoms is called Element ex. Helium, Lithium, etc. There are 118 elements discovered out of them, 32 elements •hound in nature while the remaining 26 are are elements made artifically in laboratory. Element are divided into 3 types on the basic of their physical and chemical properties. They non-metal and metalloids. metal,

8. Metal The element which are shiny, good conducter at heat and electricity, mallable and ductile element-eg. copper, iron, gold, etc.

9. Iron is a metal. Give reason. 

=Iron is a metal because they shiny malleable, ductile and are the good. ate the good conductor at heat and electricity.

10. Non-Metal :

= The Elements which are not shiny and brittle elements that do not conduct heat and electricity is called Non-Metal-ex: At room Non-Metal exist 3 state: 

-Solid-Carbon, Phosphorus, Sulphur, Iodine, etc..

ii. Liquid-Bromine

iii Gas-Hydrogen, Helium, Nitrogen Oxygen, Fluorine, etc.

:-Note Expection, Graphite is a non-metal but it conduct heat and electricity.

11. Nitrogen is a non-metal ? Why? 

= Nitrogen is a non metal because it is not shiny.

12. Metalloids-

= The Elements which show the properties. at both metal and non-metal is called metalloids. g Silicon, germanium, arsenic, antimony, etc.

13. Atom:

= The smallest particle of an element that take part in chemical reaction is called atoms.

:--Note Atom consists 3 particles that are Proton, Neutron, Electron These particles is called sub-atomic particles. Proton Proton positively change atomic particle. bolt positive charge. The mass of proton is  equal to the mass of hydrogen intern. In atomic mass, Unit mass of Proton is 1 amu. It is denoted. _by => p+

ii. Neutron-

= It is neutral sub-atomic particle present in the nucleus. It mass is nearely equal to the mass hydrogen atom Hence, the mass of Neutron is also 1 amp. It is denoted by n².

iii. Electron-

= An Election is negatively charge sub-atomic particle revolved around the nucleus of vaccum. It is the lightest be. It's mass is about 1/1837 times the mass. of hydrogen atom It is denoted by e-.

17. Electronic Configuration:

= The systematic distribution of electron around the necelous of an atom is called Electronic Configuration.

18. Significance of Electronic Contiguration. 

= They are:

i. It helps to determine the valency of an elements.

ii. It helps to determine the position of an element in the periodic table.

19. What is 2n square? 

= The maximum number at election that can remain together in a shell is given by 2n square where n is number of shell. this rule is. as 2n square rule.

20. Atomic Structure of an Atom.

= i. Potassium

Name of element Potassium.

Symbol- K 

Atomic number: 19

No. of Protons:11 

No of Neutron: 20

No. of Electron= 18

21. Octet and Octet rule. 

= The stable arrangement of sight election in the valence. shell at atoms is called actat.eg-Neon, Argon, krypton, Xenon (xe), Rondon (Rn), etc.

The tendency at an element to attain eight electron in its valence shell by gaining, Losing called octet rule.

22. Duplet and. Duplet rule. 

= The stable arrangement at two element electrons in the valence K-shell at an element is called duplet.