Advertisements
Advertisements
प्रश्न
When extremely small particles X derived from the anther of a flower were suspended in a liquid Y and observed through a microscope, it was found that the particles X were moving throughout the liquid Y in a very zig-zag way. It was also observed that warmer the liquid Y, faster the particles X moved on its surface.
- What could particles X be ?
- What do you think liquid Y is ?
- What is the zig-zag movement of X known as ?
- What is causing the zig-zag movement of particles X ?
- Name the scientist who discovered this phenomenon.
- What does this experiment tell us about the nature of liquid Y?
Advertisements
उत्तर
The particles, 'X' are pollen grains.
- The fluid, 'Y' is Water.
- The zigzag movement of 'X' is called Brownian motion.
- The zigzag motion of the pollen grains occurs because the particles of water are in constant motion. These particles collide with the pollen grains and cause them to move.
- Robert Brown is the scientist who discovered Brownian motion.
- Liquid Y is made up of extremely small particles, which are moving constantly.
APPEARS IN
संबंधित प्रश्न
What are molecules ?
Fill in the following blank with suitable words :
The best evidence that the particles of matter are constantly moving comes from the studies of ................. and ...................
State two characteristics of matter demonstrated by Brownian motion.
Bromine and air take about 15 minutes to diffuse completely but bromine diffuses into a vacuum very rapidly. Why is this so?
What are the three groups into which all the elements can be divided ? Name two elements belonging to each group.
Give reason why copper metal is used for making electric wires.
Which of the two will scatter light : soap solution or sugar solution ? Why ?
Define Foam Give one example.
One of the following is a solid foam. This one is :
Milk of Magnesia is :
Fill in the following blanks with suitable words :
A mixture of kerosene and petrol can be separated by .....................
The correct increasing order of the boiling points of liquid oxygen, liquid argon and liquid nitrogen present in liquid air is :
Which one of the following scrap metal cannot be separated by magnetic separation ?
Tincture of iodine is a mixture of two materials X and Y. The material Y has a property that its solid form can be converted directly into vapours on heating by a process called Z.
- What could X be ?
- What could Y be ?
- Name the process Z.
- Which process would you use to recover both the components X and Y from tincture of iodine ?
- Which process can be used to recover only component Y from tincture of iodine ?
The given mixture contains three constituents A, B and C. The constituent A is a yellow coloured, solid element which dissolves in a liquid D. The constituent B is a blue coloured salt which is insoluble in liquid D but dissolves easily in another liquid E. The constitudent C is a liquid which is used in cooking food and forms a solid fat on hydrogenation.
(a) What do you think could (i) constituent A, and (ii) liquid D be ?
(b) What could (i) constituent B, and (ii) liquid E be ?
(c) What could liquid C be ?
(d) How will you separate the mixture containing A, B and C ?
______ is a smallest particle.
A standard sheet of paper is about ______ of atoms thick
Atoms or groups of atoms having a charge are called ______.
Compressibility of solids: ______.
Define the term matter.
