Reviewing Std 6 Basic Science Notes Pdf English Medium and Kerala Syllabus Class 6 Basic Science Chapter 9 Mix and Separate Notes Question Answer SCERT Solutions Pdf can uncover gaps in understanding.
Basic Science Class 6 Chapter 9 Mix and Separate Question Answer Notes
Basic Science Class 6 Chapter 9 Question Answer Notes Mix and Separate
Mix and Separate Class 6 Notes Questions and Answers
Let Us Assess
Question 1.
Observe the materials given below.
i) How can you separate the components if A and B get mixed?
ii) How can you separate the components if A and C get mixed?
iii) How can you separate the components if A and D get mixed?
Answer:
i) Wax powder + iron. This mixture can be separated by magnetic separation. The magnet attracts iron from the mixture leaving behind wax powder.
ii) Wax powder + salt
The mixture of wax powder and salt can be separated by dissolving it in water, where wax powder being in soluble will not dissolve in water but salt being soluble will dissolve in water. Then ration is used to separate wax powder. By evaporation of the salt solution, we will separate salt from water.
iii) Wax + sand
The mixture of wax powder and sand can be separated by dissolving it in water, wax powder can be separated by using filtration method. Sand settles down, (decontation)
Question 2.
Using which equipment will you get water with maximum purity while filtering muddy water? Why?
a) Cloth
b) Filter Paper
c) Tea strainer
Answer:
Filter Paper, because filter paper contain small holes. These holes can separate mud from muddy water. So by using filter paper we can get water with maximum purity.
Question 3.
How does pure water differ from sugar solution based on the constituents present in them?
Answer:
Pure water is pure substance because it contains only water molecules. But sugar solution is a mixture which contains molecules of water and molecules of sugar.
MIXAND SEPARATE
Question 1.
Take a pinch of sugar examine and write its specialities like colour, odour and state.
Answer:
Colour: white or colourless
Odour : No odour
State: Solid
Question 2.
What are the three states of matter?
Answer:
Solid, liquid, gas
Question 3.
What do you mean by states of matter?
Answer:
State of matter is one of the distinct forms in which matter can exist.
Question 4.
What is a matter?
Answer:
Matter is made up of various types of particles.
Question 5.
Take a pinch of salt and examine its peculiarities?
Answer:
Salt is colourless, it has no odour and exist in solid state.
Question 6.
Anila breaks a sugar candy and made it into very small pieces. Again she breaks it and make it too small invisible to naked eye.
a) That small particles of sugar candy is…….. ?
b) Is there any change in its state and taste?
Answer:
a) molecule of sugar
b) No, its state and taste will remain the same.
Question 7.
Can we make sugar candy using sugar molecules?
Answer:
Yes. we can make sugar candy using sugar molecules.
Question 8.
Define molecule?
Answer:
The smallest particle of a substance retaining all the properties of that substance is known as its molecule.
Question 9.
What are the three states in which substances exist?
Answer:
Solid, liquid, gas
Question 10.
Substances that exist in three states are made up of….. ?
Answer:
molecules
Question 11.
Write examples of molecules?
Answer:
Water (H20), Oxygen (O2), Ozone (O3), Sodium Chloride (Nacl, table salt)
Question 12.
The smallest particle of a substance is …………?
Answer:
molecule
Question 13.
What are the properties of molecule?
Answer:
Molecule is the smallest particle of a substance.
Molecule have spaces between them.
Molecule possess kinetic energy.
Molecules are in constant motion.
PURE SUBSTANCES
Question 1.
What do you mean by pure substance?
Answer:
If a substance contains only one type of molecule it is known as pure substances.
Question 2.
Give examples for pure substance?
Answer:
Salt, Aluminium, Oxygen, Silver, Sugar
Question 3.
Does sugar a pure substance? Why?
Answer:
Yes. Sugar is a pure substance because sugar contains only sugar molecules. If a substance contains only one type of molecule. It is known as pure substance.
Question 4.
Select pure substances from below given list? Milk, Gold, Oxygen, Chlorine, Coffee, Salt,
Answer:
Pure substance: Gold, Oxygen, Chlorine, Salt.
Question 5.
Coffee is not a pure substance. Why?
Answer:
Coffee contains water, coffee powder and sugar. Pure substance contain only one type of molecule. But in coffee it contains more than one type of molecules. That is why coffee is not a pure substance.
Question 6.
Arun and Sharon both are studying pure substance. Arun told tea is a pure substance. But Sharon didnot agree with it. Who is correct and why?
Answer:
Sharon is correct. Tea is not a pure substance. Tea contains more than one type of molecules, tea powder, water and sugar.
Question 7.
Pottassium permanganate is a pure substance. When we add a pinch of KMnO4 in water taken in a beaker will it remains as pure substance? Why?
Answer:
Pottassium permanganate is a pure substance. When we add a pinch of KMnO4 to water the resultant solution contains water molecules and KmnO4 molecules. Therefore it is not a pure substance.
Question 8.
How can we classified pure substance?
Answer:
Pure substance can be classified into elements and compounds.
Question 9.
What molecules will be present in a solution made by dissolving sugar candy in water?
Answer:
Sugar molecules and water molecules.
MIXTURE
Question 1.
Define mixture?
Answer:
If there are more than one type of molecules present in a substance, it is called a mixture.
Question 2.
Give example of mixtures?
Answer:
Sugar solution, salt solution, Air, Ink, Sea water.
Question 3.
Classify below given substances into pure substance and mixtures ?
Sugar solution, soda, oxygen, chlorine, air, salt solution, ink, iron, mercury.
Answer:
Pure substance: oxygen, chlorine, iron, mercury
Mixtures: soda, sugar solution, air, salt solution, ink
Question 4.
Distinguish between pure substance and mixtures.
Answer:
Pure substance |
Mixtures |
1) contains only one type of molecule |
1) contains more than one type of molecules |
2) Physical properties are constant |
2) Physical properties vary |
3) Cannot be separated |
3) Can be separated |
Eg: Oxygen, sugar |
Eg: Air, Sugar solution. |
Question 5.
You are provided with below given substances. Make a mixture.
Beaker, Spatula, copper sulphate, crystals, water
Answer:
Take the beaker add a spatula full of CuSO4 crystals in the beaker. Add water into the beaker containing CuSO4. Stirr it well using the spatula. Then you will get a mixture of copper sulphate and water which is blue in colour.
Question 6.
Does salt solution a mixture? why?
Answer:
Yes. Salt solution is a mixture, which con-tains molecules of salt and molecules of water. A mixture contains more than one type of molecules.
Question 7.
Does ink a pure substance or mixture?
Answer:
Ink is a mixture because it contains different dyes.
Question 8.
Air is a ………..?
Answer:
Mixture
Question 9.
Complete the below given table.
Answer:
Substance |
Molecules present |
a) Sugar solution |
Sugar water |
b) Soda |
Carbon dioxide, water |
c) Air |
Nitrogen, oxygen, carbon dioxide, water vapour |
d) Copper Sulphate |
Copper Sulphate |
Different types of mixtures
Generally mixtures are of two types Homo-geneous mixtures and heterogeneous mix-tures.
Question 1.
What do you mean by Homogeneous mixtures?
Answer:
If a mixture exhibits the same property throughout that mixture is called homoge-neous mixtures.
Question 2.
Give examples for homogeneous mixtures?
Answer:
Salt solution, sugar solution, lemon juice, air
Question 3.
Write down the properties of homogeneous mixtures?
Answer:
- It has a uniform composition
- It exhibits same property throughout that mixture.
Question 4.
What is a heterogeneous mixture?
Answer:
If a mixture exhibits different properties in different parts, that mixture is called het-erogeneous mixture.
Question 5.
Write down the examples of heterogeneous mixture?
Answer:
oil and water, sand and water, chalk powder and water.
Question 6.
What are the properties of heterogeneous mixtures?
Answer:
- Composition is not uniform
- It has different properties throughout the mixture.
Question 7.
Differentiate between homogeneous mixture and heterogeneous mixture?
Answer:
Homogeneous mixture |
Heterogeneous mixture |
1) Composition is uniform |
1) Composition is not uniform |
2) Exhibit same properties throughout the mixture |
2) Exhibit different properties throughout the mixture |
3) Only one phase |
3) More than one phase |
Eg. mixture of sugar and water |
Eg. mixture of sand and water |
Question 8.
What are the different types of mixtures we get using the below given substances? sand, sugar, water, chalkpowder
Answer:
We can make different types of mixtures using the given substances.
sand + sugar mixture
sand + water mixture
sugar + water mixture
chalkpowder + water mixture
chalkpowder + sugar mixture
sand + chalk powder mixture.
Question 9.
Over consumption of tea and coffee are not healthy. But most of us like to have it. Don’t you know which type of mixture are tea and coffee? why?
Answer:
Tea and coffee are homogenous mixtures because both mixtures possess same composition and properties throughout the mixture.
Question 10.
Babitha is making homogeneous mixture and heterogeneous mixture. She told that she like homogeneous mixtures because it possess same property throughout the mixture. Then what are the properties of heterogeneous mixtures. Give examples for both type of mixtures.
Answer:
The properties of heterogeneous mixtures are
- The composition of heterogeneous mix¬ture is not uniform.
- It has different properties throughout the mixture.
eg: sand and water mixture, oil and water mixture.
Homogeneous mixture, eg: sugar solution, air.
Question 11.
Milk is a mixture?
Answer:
Heterogeneous
Question 12.
Why milk is a heterogeneous mixture?
Answer:
Milk is a heterogeneous mixture. Milk con-tains fat and water components which cannot be mixed together. Therefore milk is a heterogeneous mixture.
Question 13.
Eating salad is good for health. Does salad a homogeneous or heterogeneous mixture?
Answer:
Salad is a heterogeneous mixture of different vegetables or fruits.
Question 14.
Find out homogeneous and heterogeneous mixtures from the following. sand, milk, air, concrete, salt and pepper, sugar water, oil and water, cup of coffee.
Answer:
Homogeneous: air, sugar water, cup of coffee. Heterogeneous: sand, milk, concrete, salt and pepper, oil and water.
Question 15.
Tabulate some mixtures that you are familiar with.
Answer:
Lemon juice, karingali water, tea, coffee, milk, salad.
Different types of solutions
Question 1.
All solutions are …………. ?
Answer:
Homogeneous mixtures
Question 2.
In which states a solution exist?
Answer:
A solution exist in solid, liquid and gaseous states.
Question 3.
What is a solution?
Answer:
A solution is a homogeneous mixture of one or more solutes dissolved in a solvent.
Question 4.
Define the term solute?
Answer:
Solute is a substance that dissolves in a solvent.
Question 5.
What do you mean by solvent?
Answer:
Solvent is the substance in which other ma-terials dissolved. It is more in quantity.
Question 6.
Find out solute and solvent from the below given solutions?
Salt and solution, salt in food, oxygen in sea water, sugar in tea, carbon dioxide in carbon-ated drinks.
Answer:
Salt solution → solute → salt, solvent → water
Salt in food → solute → salt, solvent → food
oxygen in sea water → solute → oxygen, solvent → seawater
sugar in tea → solute → sugar, solvent → water
carbon dioxide in carbonated drinks → solute Co2, solvent → drinks (water)
Question 7.
What are the main components of a solution?
Answer:
Solute, solvent.
Question 8.
Can you make a solution without a solvent?
Answer:
No. solution = solute + solvent
Question 9.
What are the constituent particles present in the below given solutions?
Brass, soda, air
Answer:
Brass = Zinc and copper
Soda = carbondioxide and water
Air = Nitrogen, oxygen, carbondioxide, water vapour etc.
Question 10.
Identify the characteristics of the following solutions based on the constituent particles. Brass, soda, air, glycerine dissolved in water.
Answer:
Brass – solid dissolved in solid.
Soda – Gas dissolved in liquid
Air – Gas dissolved in gas
Glycerine dissolved in water – liquid dis-solved in liquid.
Question 11.
Find out examples for the below given solutions?
a) solid dissolved in solid
b) gas dissolved in gas
c) liquid dissolved in liquid
Answer:
a) sand in chalkpowder
b) air
c) Ethanol in water
Question 12.
The constitutent particles of brass are Zinc and ………..?
Answer:
Copper
Question 13.
Does soda is a solution? Why?
Answer:
Yes. Soda is a solution of carbon dioxide in water. Here carbon dioxide is the solute and water is the solvent. Soda is a gas dissolved in liquid solution.
Separation of mixtures
Question 1.
What do you mean by separation of mixtures?
Answer:
Separation of mixtures is the process of separating components of a mixture using physical methods.
Question 2.
What are the different physical methods of separating mixtures?
Answer:
Handpicking, threshing, winnowing, filtration, evaporation, distillation, decantation, chromatography, separating funnel etc.
Question 3.
What do you mean by decantation?
Answer:
Decantation is the process of separating the clear liquid above after sedimentation of the component of a mixture.
Question 4.
How can you separate sand from a mixture of sand and water?
Answer:
Decantation
Question 5.
Rishvi used decantation to separate sugar from sugar solution. Is it possible? Why?
Answer:
No, because decantation used to separate clear liquid above after sedimentation of the components of a mixture. Here sugar is com-pletely dissolved in water to form sugar so-lution, decantation process cannot be used here for separation.
Question 6.
Name the solutions which can be separated using decantation process?
Answer:
Oil and water, muddy water, kerosene and water, milk and cream.
Question 7.
Write down the applications of decantation?
Answer:
→ Decantation can be used to separate im-miscible liquid that have different desities.
→ Sewage treatement
→ Water purification
Question 8.
Which separation method is applied to separate muddy water?
Answer:
Decantation process
Question 9.
Is the water obtained after decantation clear?
Answer:
No
Making water clear
Question 1.
Some materials are given below which material is suitable to get water which is more clear.
Funnel, Tea strainer, Filter paper, cloth piece, Bamboo basket.
Answer:
Filter paper
Question 2.
What is filter paper?
Answer:
Filter paper is a semi-permeable paper bar-rier placed perpendicular to a liquid or air flow.
Question 3.
What are the used of filter paper?
Answer:
Filter paper is used to separate components from air or liquid flow. Used for separating solid from liquid.
Question 4.
Different types of sieves used to separate … sand during construction of buildings. What is the reason for this?
Answer:
Sieves are used at construction sites to separate pebbles and stones from sand. Sieving is used to separate substances that are of different sizes. The smaller components of the mixture can pass through the pores of the sieve whereas bigger components of the mixture are retained by the sieve.
Question 5.
What property of the substance is made use of when the constituents of a mixture are separated using a sieve?
Answer:
Depends upon the difference in size of the particles.
Question 6.
What do you mean by filtration?
Answer:
Filtration is the process of separating the constituent particles of a mixture using a sieve.
Question 7.
How can you separate the consituents of a mixture of chalk powder and water? What all the materials are required?
Answer:
Chalk powder and water form a heterogeneous mixture. Chalk powder does not mix with water. We can separate this mixture by filtration.
Materials required: Funnel, Filter paper, beaker, chalk powder and water mixture. Procedure: Take a filter paper and make it in the shape of funnel. Place the filter paper on the mouth of a funnel. Take a beaker and place the funnel at the mouth of the beaker. Check the filter paper is properly placed. Then slowly pour the mixture on the filter paper.
Observation: Water will pass through and the chalk powder will remains of the filter paper. Chalk powder is collected as a residue on the filter paper.
Question 8.
Which is the good sieve to separate a mixture of chalk powder and water? Why?
Answer:
Filter paper, because chalk powder is in-soluble in water. So chalk powder is collected as a residue on filter paper and water is collected as a filtrate.
Question 9.
What do you mean by filtrate?
Answer:
Filterate is a liquid substance obtained after filtration.
Question 10.
What do you mean by residue?
Answer:
In the filtration process, the solid particles left on the filter paper are called residue.
Question 11.
Who is the biological filter in our body?
Answer:
Kidneys
Question 12.
Find out the filtrate and residue after filtration of the following mixtures?
Chalk powder and water mixture, muddy wa¬ter after decantation, Tea.
Answer:
a) Chalk powder and water
Filtrate : Water
Residue: Chalk powder
b) Muddy water after decantation
Filtrate : clear water
Residue : tiny sand particles
c) Tea
Filtrate : Tea
Residue: Tea leaves
Separation of dissolved components
Question 1.
What is evaporation?
Answer:
Evaporation is the process by which a liquid absorbs heat and gets converted to vapour.
Question 2.
Can you separate salt from salt solution using a sieve?
Answer:
No
Question 3.
How is salt separated from sea water?
Answer:
Evaporation is used to separate salt from sea water. Sea water is collected in shallow pits. After some days, the water evaporates by absorbing heat from sun leaving behind the salt. This salt is collected and further processed and purified.
Question 4.
Which mixtures can be separated into constituents through evaporation?
Answer:
Salt from salt water, sugar from sugar solu-tion copper sulphate crystals from copper sulphate solution.
Question 5.
Which is the source of heat required to evaporate water in salt pans?
Answer:
Sunlight
Question 6.
Write some examples of evaporation from our daily life situations?
Answer:
- Drying clothes in the sun.
- Drying of a mopped floor.
- Drying of wet hair.
- Evaporation of sweat from body
Question 7.
Write down the applications of evaporation?
Answer:
- Used on large scale to obtain common salt from sea water.
- Evaporation plays a very important role in the water cycle.
- Used to remove water from dilute liquid foods.
- Used in food processing industries to remove water from a food product.
Question 8.
Which method is applied to separate the constituent particles from sugar solution? How?
Answer:
Evaportion
Heat sugar solution taken in a beaker water will evaporate leaving behind sugar.
Separating Iron powder
Question 1.
How can you separate iron powder from aluminium powder from a mixture?
Answer:
Using a magnet. Iron powder get attracted by the magnet and aluminium powder remains the mixture.
Question 2.
How will you separate a mixture of iron powder and Sulphur powder? What property of iron powder will make use?
Answer:
We can separate the mixture of iron powder and sulphur powder using magnet. Iron pow¬der will get attracted by the magnet and sulphur powder remain the mixture. The magnetic properties of iron powder we make use of.
Question 3.
How will you separate oil from coconut at home?
Answer:
Remove the shell of coconut and make coconut milk. Heat the mixture, then the water content from the mixture get evaporaed leaving behind oil.
Question 4.
What method is used in our homes to separate copra cakes from coconut oil?
Answer:
Keep the coconut oil undisturbed for few days. We can see that copra settled down at the bottom.
Sand as a good sieve
Question 1.
Why is the water in wells clear?
Answer:
Water in wells is clear due to the natural filtration by the sand.
Question 2.
Is there any chance for the water in the well to get contaminated if the septic tank is close to the well?
Answer:
Yes, there is a chance for contamination.
Question 3.
How can septic tanks contaminate water in the well?
Answer:
The untreated wastewater contains pathogens and harmful substances which directly get into the ground water or well water.
Question 4.
Can a septic tank be closed to a well?
Answer:
To protect our drinking water quality do not locate septic tank or other contaminate sources close to well.
Question 5.
Is sand purify water? How?
Answer:
Yes. As water flows slowly through the sand the unwanted substances get filtrated through the layers of sand. Thus get filtered and purified.
Question 6.
Does sand is used for water purification?
Answer:
Yes
Common methods of separating substances or mixtures
Handpicking, threshing, winnowing, evaporation, distillation, filtration or sedimentation, separating funnel, chromatorgraphy, magnetic separation are the methods of separating mixtures.
Question 1.
What do you mean by handpicking?
Answer:
It is the process used to separate slightly larger particles from a mixture by hand, eg: Stone pieces can be separated from wheat or rice by handpicking.
Question 2.
What is threshing?
Answer:
It is the process of separating grains from stalks by beating dry stalks to shake off the dried ones.eg: separation of wheat, rice from dry stalks.
Question 3.
What do you mean by winnowing?
Answer:
Winnowing is the method in which heavier component of the mixture are separated from the lighter substances with the help of wind, eg: The wheat and husk mixture is dropped from a height. Husk is lighter than wheat grains, it is removed from wheat by wind or air.
Question 4.
What do you mean by distillation?
Answer:
Distillation is the process of separating the components from a liquid mixture by using selective boiling and condensation, eg: purification of alcohol.
Question 5.
What is a separating funnel?
Answer:
A separating funnel is used to separate two immiscible liquid.
Question 6.
What is chromatography?
Answer:
Chromatography is the process of separat¬ing components of a mixture, eg: separation of components of ink.
Question 7.
Complete the concept map by writing the methods employed and cite examples.
Answer:
Mix and Separate Class 6 Notes
The smallest particle of a substance retain¬ing all the properties of that substance is known as molecule. Substance that exist in the solid, liquid and gaseous states are made up of mol¬ecules. There are different types of molecules, monoatomic, diatomic and polyatomic mol-ecules. All these types are differ in the number of atoms that present in each molecule. There are pure substances and mixtures too. Salt, oxy¬gen, copper, silver etc are pure substances, where as sugar solution, salt solution, Air, soda etc are mixtures. The different types of mixtures are ho-mogeneous and heterogenous mixtures.
A solution is formed by the mixing up of solute and solvent all solutions are homogeneous mixtures. All solutions do not exist in liquid state. Solutions also exist in solid and gaseous states. When we discussed about mixtures and solutions it is necessary to learn about the separating method when we want to separate the constitu-ents of a solution it is Very useful. There are dif-ferent types of separating methods are available. Each method depends upon the nature of con-stituent particles that present in the solution or any other. Decantation, Filtration, Evaportation, magnetic separation, seiving, distilliation etc are some of the separation methods.
All substances are not present in their pure form in nature. Most of the substances are present in the form of mixtures. We can sepa¬rate the useful components of the mixtures by using various methods of separation. By separating the constituents of the mixtures we are able to find out the properties of the known/unknown substances from mixtures. We can use this for the production of useful substances. Depending on the physical and chemical properties of the substance we can choose the correct separation technique.