is matter around us pure?

Question 1

pure substance-

Answer 1

all the constituent particles of that substance are the same in their chemical nature

Question 2

mixtures-

Answer 2

more than one kind of pure form of matter

Question 3

solution-

Answer 3

it is a homogeneous mixture of 2 or more substances

Question 4

mixtures have _________composition

Answer 4

variable

Question 5

what are alloys?

Answer 5

mixtures of 2 or more metals or a metal and a non-metal

cannot be separated by physical methods

Question 6

brass composition-

Answer 6

30%zinc 70%copper

Question 7

a solution is made of _______ and _________

Answer 7

solute and solvent

Question 8

what is a solvent?

Answer 8

the component of the solution that dissolves the other component in it (usually present in larger amount) is called the solvent

Question 9

solute-

Answer 9

the component of the solution that is dissolved in the solvent (usually present in a smaller quantity) is called solute

Question 10

the size of the particles of a solution are _______ in size

Answer 10

smaller than 1 nm

Question 11

a solution __________a beam of light

Answer 11

does not

Question 12

a solution is ________ (stable/unstable)

Answer 12

stable

Question 13

a solution cannot be seperated by _______

Answer 13

filteration

Question 14

saturated solution-

Answer 14

at any particular temperature, a solution that has dissolved as much solute as it is capable of dissolving is called a saturated solution

Question 15

solubillity is-

Answer 15

the amount of solute present in the saturated solution at this temperature is called its solubility

Question 16

unsaturated solution is-

Answer 16

amount of solute contained in a solution is less than the saturation level it is called unsaturated solution.

Question 17

different _________ in a given solvent have different ___________at the same temperature

Answer 17

substances, solubilities

Question 18

a suspension is a __________ (homogeneous/heterogenous)

Answer 18

heterogenous

Question 19

what is a suspension?

Answer 19

when solute particles do not dissolve but remain suspended through the bulk of the medium

Question 20

the particles of a suspension __________(are/are not) visible to the naked eye

Answer 20

are visible

Question 21

the particles of a suspension _________a beam of light

Answer 21

scatter

Question 22

a suspension is __________(stabke/unstable)

Answer 22

unstable (particles settle down)

Question 23

a suspension can be separated through filtration- (true false)

Answer 23

true

Question 24

a colloidal solution is _______ spread throughout the solution

Answer 24

uniformly

Question 25

a collidal solution is a _________ mixture(homogeneous/heterogenous)

Answer 25

heterogenous

Question 26

a collidal solution has relatively ______particles which _____ be see through a naked eye (can/cannot)

Answer 26

small particles, cannot

Question 27

a collidal solution _________(does/does not) scatter a beam of light

Answer 27

does

Question 28

a collidal solution is _______(stable/unstable)

Answer 28

stable

Question 29

what is tyndall effect?

Answer 29

scattering of a beam of light

Question 30

heterogeneous -

Answer 30

non uniform throughout, can be serpated by physical methods

Question 31

homogenous is-

Answer 31

uniform throughout

Question 32

how can dye be separated from blue/black ink?

Answer 32

by evaporation

Question 33

how to separate cream from milk?

Answer 33

centrifugation

Question 34

how to seperate mixture of 2 immicible liquids like kerosene oil and water?

Answer 34

seperating funnel

Question 35

how to seperate mixture of salt and camphor?

Answer 35

sublimation

Question 36

how to know if dye in black ink a single colour?

Answer 36

chromatography

Question 37

what is chromatography?

Answer 37

separation of solutes that dissolve in the same solvent

Question 38

how to seperate mixture of 2 miscible liquids?

Answer 38

distillation

Question 39

when is simple distillation used?

Answer 39

when there is a sufficient difference in the boiling points

Question 40

when is fractional distillation used?

Answer 40

when the difference in boiling points is less than 25 degree kelvin

Question 41

what is a fractioning coloumn?

Answer 41

it is a tube packed with glass beads | the beads provide surface for vapors to cool and condense

Question 42

how to compress air?

Answer 42

increasing pressure and decreasing temperature

Question 43

how to seperate pure copper sulphate from an impure sample?

Answer 43

crystallisation

Question 44

when is crystallisation used?

Answer 44

to purify solids

Question 45

how was the first scientist to use the term 'element' and when?

Answer 45

robert boyle, in 1661

Question 46

who was the man who defined element?

Answer 46

Antoine laurent lavoisier

Question 47

what it is an element?

Answer 47

a basic form of matter that cannot be broken down into simpler substances by chemical reaction

Question 48

what is a compound?

Answer 48

it is a substance composed of two or more element chemically combined with one another in a fixed proportion

Question 49

simplest form of compounds

Answer 49

molecules

Question 50

a liquid non metal at room temperature

Answer 50

bromine

Question 51

what is concentrated solution?

Answer 51

solution with high solute concentration

Question 52

hydrogen gas is -

Answer 52

colourless, odourless, combustible

Question 53

size of particles in a collide are-

Answer 53

between 1nm and 100nm

Question 54

size of particles of a suspension are-

Answer 54

greater than 100 nm

Question 55

what are aquenous solutions?

Answer 55

when the solvent is water, the solution is known as aquenous solution

Question 56

what are non-aquenous solutions?

Answer 56

when the solution is any other liquid other than water then the solution is known as non aquenous solution

Question 57

the continous zig zag movement of collidal particles in a dispersion medium is called?

Answer 57

brownian movement

Question 58

how many types of collides are there?

Answer 58

8

Question 59

how to separate a colloidal solution?

Answer 59

centrifugation

Question 60

gas + liquid=

Answer 60

foam (shaving cream)

Question 61

liquid +liquid=

Answer 61

emulsion (milk,face cream)

Question 62

solid +liquid=

Answer 62

sol (milk of magnesia, mud)

Question 63

gas+solid=

Answer 63

foam (rubber, sponge)

Question 64

solid +solid=

Answer 64

solid sol (colored gemstone, milky glass)

Question 65

liquid+solid=

Answer 65

gel (jelly, cheese, butter)

Question 66

liquid+gas=

Answer 66

aerosol (fog,clouds,mist)

Question 67

solid+gas=

Answer 67

aerosol (smoke, automobile exhaust)