SARAH MUSHEER
A mixture is made when two or more substances are combined, but
they are not combined chemically. "Not chemically combined"
means that no chemical reaction happens when the substances are
mixed. And thus can be separated in most cases
Mixture may be a element, compound or both. They can be solid,
liquid or gases mixed together to form a mixture.
Think of this as a bag of mixed candy bars. Just because the candies are
mixed together in the bag does not mean that the Kit-Kats and Snickers
fuse together to become some absurd new candy. They keep their own
properties (flavors, ingredients) because they are not chemically
combined.
General properties of mixtures:
 The components of a mixture can be easily separated
 The components each keep their original properties
 The proportion of the components in a mixture is variable
5. A compound generally has A mixture has no definite
a fixed melting and boiling
melting or boiling point.
point.
Mixtures are divided into two types ( homogeneous mixtures and
heterogeneous mixtures)
 In homogeneous mixture, the components are evenly distributed throughout and
the mixture has a uniform appearance. You shouldn't be able to pick out the
individual components. example: puree, coffee, milkshake, tomato soap, air
 A heterogeneous mixture has components that are not evenly distributed. This
means that you can easily distinguish between the different components.
Example : trial mix, ice in water, oil in water
 Crude oil: A mixture of organic compounds (mainly hydrocarbons)
 Seawater: A mixture of various salt and water.
 Air: a mixture of various gases like oxygen, carbon dioxide, nitrogen, argon, neon,
etc.
 Ink: A mixture of colored dyes.
 Gunpowder: A mixture of sulfur, potassium nitrate and carbon.
 Blood: a mixture of plasma and red blood cell that can be separated through a
process called centrifuge.
Alloy is a metal made from the
combination of two or more metallic
elements. When these metallic
elements are combined, they usually
form something with greater
strength than the metals have
individually. All alloys are made up
of different metals and have metallic
properties.
EXAMPLES:
• Gold + silver + copper= rose gold
• Carbon + iron= steel
Q1. Nowadays most people use tea bags to make tea, but there was a time when people brewed
tea from leaves and then poured the tea through a sieve into the cup. Why do you think they did
this?
Q2. Sometimes the particles that we want to remove from a mixture are so small that they will
pass easily through a sieve (think of the example of the muddy water). Can you think of a way to
overcome this?
Mixtures contain different substances that are not combined together chemically. Thus it can
be separated through different techniques.
 Boiling
 Condensation
 evaporation
 Filtration
 Sieving
 Simple distillation
 Fractional distillation
 Chromatography
 Magnetism
 Hand picking
It is the process to remove insoluble solid from liquid by using a filter paper. The clear liquid
obtained is called filtrate. The solid that remains in the filter paper is called residue.( a
mixture of chalk powder and water , mixture of sand and water)
This method is used in:
 water treatment plants
 Kidneys are the biological filter
 Brewing coffee
 Air conditioner
 Vacuum cleaner
Advantages:
 cost effective
 Maintenance is low
Disadvantages:
 germs and contaminants are not removed from filtered water.
 Micro-particles can pass through the membranes.
DIY EXPERIMENT 1:
HTTPS://WWW.YOUTUBE.COM/WATCH?APP=DESKTOP&V=ICYNTIU7R6I
Mixtures of different color dyes or inks can be separated
using chromatography. Lets suppose we put a small drop of
ink into the paper. As the water moves up the paper, the colors
in the ink will start to separate out . The colors separate
because the water dissolves the ink . As the water moves up it
carries the particles of ink with it.
Advantages:
 Efficient technique
 Most widely used method in pharmaceutical industry and in
the food industry
 It requires the small amount of sample for the analysis
Disadvantages:
 Time consuming
 Complex mixtures can not be separated
 Large sample can not be conducted
FILTER PAPER ART CHROMATOGRAPHY:
https://www.youtube.com/watch?v=sbG2gn83LUo
Distillation is not a naturally occurring process. It is used to separate mixture
of liquids. The process includes boiling a liquid that travels along the tube of
condenser and then collecting the vapors as it cools and condenses back into
liquid form. ( liquid-gas-liquid)
Distillation is used :
 Salt water is turned into fresh water
 Various forms of fuels are separated from crude oil
 Alcoholic beverages are made through distillation
Advantages:
 Wastage of water will be minimum
 Low heat energy
 Cheap process of production
 Simpler steps
Dis-advantages:
 Large amount of energy is needed to conduct distillation on a larger scale
 Distilling water remove all the minerals
 Time consuming
Simple distillation is useful only when a small amount of impurity is present or
when the liquids to be separated have widely different boiling point.
It is the process of heating up a mixture containing different substances with different
boiling point. Thus we can separate liquid mixture using a fractionating column. Vapors
from a boiling solution are passes along the column. The temperature of the column
gradually decreases along its length. Components with a higher boiling points condense
on the column and return to the solution. Components with a lower temperature pass
through the column and are collected.
 Ex: from crude oil we can use fractional distillation to separate mixtures upon heating
them in a furnace.
1. Butane propane 20 degree
2. Petrol 150 degree
3. Kerosene 200 degree
4. Diesel 300 degree
5. Fuel oil 370 degree
6. Lubricating oil , paraffin wax. Asphalt 400 degree
Boiling: boiling is similar to evaporation because both processes turn a liquid into a
gas. However , when a liquid is boiled, molecules gain more energy and the vapor
pressure is more than atmospheric pressure.
Evaporation: evaporation is the process by which a liquid turns into gas. Heat is
necessary for evaporation to occur. Evaporation occurs when the rate of evaporation
exceeds the rate of condensation (sweating, rain-cycle , wet clothes in the sun ).
 Example : If I put mixture of water and sulfate in room temperature, water will
evaporate into the air and leaves the copper sulfate behind
Condensation: it is opposite of evaporation . It is the change in the state of water from
gaseous state to liquid . It takes place when vapor in the warm air meets a cool
surface.(morning dew, foggy breath, foggy windshield)
Magnetism: It is the process of separating components of mixtures by using
magnets to attract magnetic materials.
 Example : If iron and sulfate are mixed together , iron being a metal can be
extracted out with the help of magnet
YOU DO STEM X ACTIVITY 1:
https://www.youtube.com/watch?v=b3HS_woWaJQ
FUNFACT:
CORN-STARCH
SUSPENSION IS AN
EXAMPLE OF NONNEWTONIC FLUID
CORN-STARCH-WATER SUSPENSION EXPERIMENT 2:
https://www.youtube.com/watch?v=5Gj224cgYyw
A solution forms when one substance dissolves in
another. The substance that dissolves is called the
solute. The substance that dissolves it is called the
solvent.
Solutes and solvents may be any state of matter.
On adding a solid substance in a liquid and
stirring it, the solid dissolves in the fluid. But when
added more and more solid to the liquid, a point
comes after which no more solid dissolves in the
liquid. This point is called a saturation point and
the fluid is called a saturation solution.
MASS OF SOLUTE + MASS OF SOLVENT = MASS
OF SOLUTION
5G + 10G= 15 G
 Solubility is a measure of how much of a solute will dissolve in amount of solvent
Solubility depends upon:
1.
Hot /cold a solvent
2.
Temperature
3.
Stirring
4.
Size of the particle
5.
Amount of the solute
 Solutions
 Suspension
Homogeneous in nature
Heterogeneous in nature
When left to stand, solute does not
separate from solvent
When left to stand, insoluble particles
sink to the bottom of the container
When filtered no residue is found
When filtered residue is collected on
the filter paper
Example : sugar solution, salt solution
Example: oil in vinegar, sand in water,
Italian dressing, medicines, orange
juice.
Q WHAT TYPE OF SOLUTION IS FORMED WHEN TWO LIQUIDS DO NOT MIX?
(miscible)
Q1. Identify homogeneous and heterogeneous
mixture by looking at the picture.
Q2. Identify solute , solvent and solution by looking
at the picture.
 Acid neutralizes bases ( acids and alkalis are chemical opposite therefore cancel
out the affect of each other)
 PH level is less than 7
 Forms H+ ions in solution
 Acids can be diluted with water to make them less corrosive or harmful
 Strong acids are poisonous and corrosive to skin
 Sour in taste
 Example : lemon, vinegar, tomatoes, oranges
Strong acids: ( ionizes completely)
 Sulphuric acid (car
batteries)(H2SO4)
Weak acids ( do not ionizes
completely)
 Acetic acid (vinegar)(HC2H3O2)
 Nitric acid (explosives)(HNO3)
 Carbonic Acid (soda) (HCO3)
 Hydro-chloric acid (stomach acid)
 Boric acid
(Hcl)
 Phosphoric acid (flavoring ) (H3PO4)
 A substance that releases –OH ions in a solution
 Bitter in taste
 Soapy to touch
 PH is greater than 7
 Neutralizes acids ( acids and alkalis are chemical opposite therefore cancel out the
affect of each other)
 Strong bases are poisonous and corrosive to skin
 Alkaline can be diluted in water to make them weak bases.
 Example: soap, batteries, sea water, detergents, shampoo.
Strong base :
Weak base:
 Lithium hydroxide
 Carbonate
 Sodium hydroxide ( drain cleaner)
 Ammonia ( some bases don’t have –OH
 Potassium hydroxide
 Calcium hydroxide
like ammonia)
 Sodium carbonates
Acids and bases can cancel each other out. When you mix them together. They make
a neutral solution.
Example:
 Hcl + NaOH = H2O+Nacl
 HNO3 +KOH = H20+KNO3
PH stand for “potential hydrogen”. It is the measure of how many H+ ions are there in any
solution. Or we can say that it measure how acidic or alkaline a substance is. Greater no.
of H+ present means the lower the PH will be
0-14 (at zero- high H+ concentration) (at 14 – low H+ concentration)
1. mouth PH – around 7
2. stomach PH – around 2
3. small intestine PH – around 8
Universal indicator tells us how acidic or alkaline a substance is. It changes to different
color in different PHs. However the strength of acids and alkalis is measured on the PH
scale .
Litmus ( it is a dye made from a living organism) paper is a common indicator that turns
red in acid , blue in bases and purple if a substance is neutral.
Q1 WHY PICKLES ARE NOT STORED IN METAL CONTAINERS?
Q2 WHY IS TOOTHPASTE ALKALINE AND WHAT IS THE CAUSE OF TOOTH DECAY
Q3 WHAT DO FARMERS SPREAD ONTO ACIDIC SOIL? EXPLAIN WHYY THEY DO IT.
 https://wordwall.net/resource/778020/separation-techniques
 https://wordwall.net/resource/817651/separation-techniques
 https://wordwall.net/resource/8239080/alloys-true-or-false
 https://wordwall.net/resource/865289/types-mixtures
 https://wordwall.net/resource/8063060/science/acidic-or-alkaline