Is Matter Around Us Pure Science - Is Matter Around Us Pure

The number of phases present in a true solution is:

The property/ properties which enable copper metal to be used for making electric wires is / are:

The principle behind fractional distillation technique in separation of two liquids is :

You are provided with a mixture of petroleum and water. You can separate this mixture by_____?

You are given a mixture of iodine in alcohol called tincture iodine. Which method will you use to recover both, iodine as well as alcohol, from this mixture?

White gold used in jewellery contains two elements, gold and palladium. A jeweller has two different samples that are both identical in appearance and have a uniform composition throughout. What can be said about the samples?

Which property of colloids is not dependent on the charge on colloidal particles:

Which one of the following statements is incorrect:

In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: Dust particle in air form aerosol.
Reason: Dust particles form dispersion medium and air is dispersed phase.

In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:

1. Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
2. The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
3. Assertion is true but the Reason is false.
4. The statement of the Assertion is false but the Reason is true.

Assertion: Dust particle in air form aerosol.
Reason: Dust particles form dispersion medium and air is dispersed phase.

In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R).
Mark the correct choice as:

1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
3. If Assertion is true but Reason is false.
4. If Assertion is false and Reason is true.
5. If both Assertion and Reason are false.

Assertion: Tyndall effect is an optical property.
Reason: Scattering of beam of light by the colloidal particles is known as Tyndall effect.

In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R).
Mark the correct choice as:

1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
3. If Assertion is true but Reason is false.
4. If Assertion is false and Reason is true.
5. If both Assertion and Reason are false.

Assertion: Colloidal particles do not show Tyndall effect.
Reason: Colloidal solutions are stable and the colloidal particles do not settle down.

In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R).
Mark the correct choice as:

1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
3. If Assertion is true but Reason is false.
4. If Assertion is false and Reason is true.
5. If both Assertion and Reason are false.

Assertion: A mixture of acetone and methanol can be separated by fractional distillation.
Reason: The difference between boiling point of acetone and methanol is very less.

Gases can be liquified at low temperature and low pressure.

State whether the following statements are true or false:

1. Bread is an example of solid foam.

2. Sponge is an example of solid sol.

What type of colloids are bread and sponge?

Name one pair of liquids which can be separated by using a separating funnel.

State whether the following statement is true or false:
Milk is a pure substance.

Sea water is a mixture.

The process of getting pure solid by cooling hot saturated solution is called ________.

Physical changes are generally..........

Mixture of ammonium chloride and sodium chloride can be separated by _______.

Fill in the following blanks with suitable words:
The three important metalloids are __________ and __________.

Fill in the following blanks with suitable words:
The separation of liquids by fractional distillation is based o the difference in their __________.

Energy changes occur during ........... change.

Fill in the following blanks with suitable words: The separation of liquids by fractional distillation is based o the difference in their __________.

The process of getting pure solid by cooling hot saturated solution is called ________.

Fill in the following blanks with suitable words:
The gases of air can be separated by fractional distillation of liquid air because they have different ___________.

Fill in the following blanks: Milk is a ________ solution but vinegar is a ________ solution.

State whether the following statements are true or false:
Alcohol can be separated from a mixture of alcohol and water by a separating funnel.

Sea water is a mixture.

State whether the following statement is true or false:

Milk is a pure substance.

Name one pair of liquids which can be separated by using a separating funnel.

Gases can be liquified at low temperature and low pressure.

Name the source from which nitrogen and oxygen are obtained on a large scale.

Is mixture a pure substance?

Name a metal:
Which has a low melting point.

Name the technique to separate Camphor from salt.

What are pure substances? Give two examples of pure substances.

Write the dispersed phase and dispersion medium present in foam. Give an example.

Write one property of colloids.

Whose one of the allotropic forms is a good conductor of electricity. Name the allotrope.

Which type of elements, metals or non-metals, show the property of brittleness?

Which technique is used in a washing machine to squeeze out water from wet clothes while drying?

What will happen if a saturated solution is: (i) heated, and (ii) cooled?

Define:

1. Solute
2. Solvent

What are solute and solvent in aerated drinks?

What would you observe when: An aqueous sugar solution is heated to dryness.

Suggest separation technique(s) one would need to employ to separate the following mixtures: Mercury and water.

You have been given a suspension and a solution. How could you tell the difference between them by their appearance?

You are provided with a solution of salt in water in one jar and mixture of salt and sand in other. Can you state one property in which they resemble and differ from one another.

You are given two samples of water labelled as ‘A’ and ‘B’. Sample ‘A’ boils at 100°C and sample ‘B’ boilsa 102°C. Which sample of water will not freeze at 0°C? Comment.

You are given two liquids, one a solution and the other a compound. How will you distinguish the solution from the compound?

Write two applications of centrifugation techniques.

How will you separate a mixture of sodium chloride and sand?

Which separation techniques will you apply for the separation of the following?

1. The different pigments from an extract of flower petals.
2. Butter from curd.
3. Oil from water.
4. Tea leaves from tea.
5. Iron pins from sand.
6. Wheat grains from husk.
7. Fine mud particles floating in water.

What type of mixtures are separated by the technique of crystallisation?

Melting of wax is a physical change but burning of wax is a chemical change. Explain.

You are provided with soda water, milk and muddy water. How can you differentiate between them in terms of:

1. Homogeneity.
2. Filtration.
3. Tyndall effect.

Write the steps you would use for making tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Write a method to separate a mixture of sand and potash alum.

While diluting a solution of salt in water, a student by mistake added acetone (boiling point 56°C). What technique can be employed to get back the acetone? Justify your choice.

Which separation techniques will you apply for the separation of the following? 

1. The different pigments from an extract of flower petals.
2. Butter from curd.
3. Oil from water.
4. Tea leaves from tea.
5. Iron pins from sand.
6. Wheat grains from husk.
7. Fine mud particles floating in water.

How can you obtain pure water from a salt-water mixture (or salt-solution)? Draw a meat and labelled diagram of the apparatus you would use to obtain pure water from a salt-water mixture (or salt-solution).

Explain how, nitrogen, oxygen and argon gases are separated form air.

With the help of a labelled diagram, describe the method of separating ammonium chloride from a mixture of ammonium chloride and common salt. Mention the difference in the properties of ammonium chloride and sodium chloride which has made this separations possible.

How is water purified on a large scale at water works? Explain with the help of a labelled diagram. Name the substance which is added to kill germs in the drinking water supply?

A child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in figure. The filter paper was removed when the water moved near the top of the filter paper.

(i) Identify the technique used by the child.

(a) Sedimentation

(b) Filtration

(c) Chromatography

(d) Distillation

(ii) What would you expect to see, if the ink contains three different coloured components?
(a) We will not see any band on the filter paper.
(b) We would see three bands on the filter paper at various lengths.
(c) We would see infinite bands on the filter paper.
(d) We would see single band on the filter paper.

iii) Give one application where you can use this technique.
(a) To separate salt from sand
(b) To separate wheat from husk
(c) To separate oil from water
(d) To separate drugs from blood.

(iv) For the separation of what kind of substances is the above process used ?
(a) For the separation of insoluble substances
(b) For the separation of single solute that dissolves in single solvent.
(c) For the separation of those solutes that dissolve in the same solvent.
(d) For the separation of those solutes that dissolve in the different solvents.

(v) What is chromatography ?
(a) It is an agricultural method to separate grains
(b) A method to separate magnetic impurities from non-magnetic impurities
(c) The process of separating the suspended particles of an insoluble substance
(d) Method of separating and identifying various components in a mixture, which are present in small trace quantities.

When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water.

1. What type of change occurs when solid A is dissolved in water? Why?
2. What type of change occurs when sold D is dissolved in water? Why?
3. Name a metal which you think could behave like solid A. Also name the products B and C.
4. Name the solid D if it is the one which is used in making ordinary dry cells.
5. Name the process by which D can be recovered from E.

Many indigestion mixtures are suspensions. What do the instructions written on the bottle of an indigestion mixture tell us before taking the mixture, and why?

You are provided with a mixture containing sand, iron filings, ammonium chloride and sodium chloride. Describe the procedures you would use to separate these constituents from the mixture?

You are given a mixture of water, groundnut oil and common salt. How will you separate groundnut oil and common salt from it?

With the help of a labelled diagram, describe the method of separating ammonium chloride from a mixture of ammonium chloride and common salt. Mention the difference in the properties of ammonium chloride and sodium chloride which has made this separations possible.

Which separation techniques will you apply for the separation of the following?

1. Sodium chloride from its solution in water.
2. Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
3. Small pieces of metal in the engine oil of a car.
4. Different pigments from an extract of flower petals.
5. Butter from curd.
6. Oil from water.
7. Tea leaves from tea.
8. Iron pins from sand.
9. Wheat grains from husk.
10. Fine mud particles suspended in water.

What is fractional distillation? What is the use of fractionating column in fractional distillation?