Advertisements
Advertisements
प्रश्न
Fill in the following blank :
A colloid is a ..............mixture and its components can be separated by the technique known as ...............
Advertisements
उत्तर
A colloid is a heterogeneous mixture and its components can be separated by the technique known as centrifugation.
APPEARS IN
संबंधित प्रश्न
Select the correct alternative
The molecules can move freely anywhere in
- gases
- liquids
- solids
- none of the above
Fill in the blank :
The substances which can flow are called ________
Classify the following into elements, compounds and mixtures:
- Sodium
- Soil
- Sugar solution
- Silver
- Calcium carbonate
- Tin
- Silicon
- Coal
- Air
- Soap
- Methane
- Carbon dioxide
- Blood
Name the scientist who studied the movement of pollen grains suspended in water through a microscope. What is this phenomenon known as?
Name a metal which has no fixed shape.
Iron powder and sulphur powder were mixed together and divided into two parts A and B. When part A was heated strongly over a burner, then a substance C was formed. The part B was, however, not heated at all. When dilute hydrochloric acid was added to substance C, then gas D was evolved and when dilute hydrochloric acid was added to part B then gas E was evolved.
- What type of substance is B ?
- What type of substance is C ?
- Name the gas (i) D, and (ii) E ?
- State one characteristic property of gas D.
- Write one test to identify gas E.
There are three substances X, Y and Z. The substance X does not have a fixed melting point or boiling point and it still shows the individual properties of its constituents. The substance Y is a pure substance which occurs in nature as such. The substance Y has a fixed melting point and boiling point but it cannot be broken down into simpler substances by any chemical means. The substance Z is also a pure substance whose properties are entirely different from those of its constituents. The substance Z can, however, be divided by electrolysis into two substances which belong to the same class of substances as Y.
- What type of substance could X be ? Name one substance like X.
- What type of substance could Y be ? Name one substance like Y.
- What type of substance could Z be ? Name one substance like Z.
- Which process involves absorption or release of an appreciable amount of energy : formation of substance X or formation of substance Z ?
- Name the three groups into which all the substances like Y are divided on the basis of their properties.
Choose one term from the following which includes the other three :
aerosol, emulsion, colloid, sol
Which of the following are chemical changes and which physical ? Give reason.
- a glass bottle breaking
- coal burning in air
- making a cake
- wool being knitted into a sweater
What type of magnet is fitted on a crane to separate scrap iron objects from a heap of waste materials in factories ?
Name the process by which the various gases of the air are separated.
Name the process you would use to separate a mixture of water and alcohol.
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..............
How will you separate a mixture of iron filings and powdered carbon ?
How will you separate water from mustard oil ?
Which of the following cannot be separated from air by the process of fractional distillation ?
Asmita went to buy an earthen pot. There she saw many things kept for sale.
What is the difference between a substance and an object?
Stars including Sun are covered in ______.
Higher the temperature, the higher the kinetic energy of particles.
Evaporation does form bubbles.
