Advertisements
Advertisements
प्रश्न
What is meant by saying that metals are lustrous ?
उत्तर
Metals are said to be lustrous because of their property to shine.
APPEARS IN
संबंधित प्रश्न
What is meant by saying that metals are sonorous ?
What elements do the following compounds contain ?
Sugar, Common salt
What is meant by (i) elements (ii) compounds, and (iii) mixtures ?Write down the names of two elements, two compounds and two mixtures.
Which of the following are compounds ?
- CO
- No
- NO
- Co
Which of the following statements are true for pure substances ?
- pure substances contain only one kind of particles
- pure substances may be compounds or mixtures
- pure substances have the same composition throughout
- pure substances can be exemplified by all elements other than nickel
Classify the following into true solutions and colloidal solutions:
Ink, Salt solution, Starch solution, Blood, Sugar solution
Define solubility of a substance. How does it vary with temperature ?
Milk of Magnesia is :
State whether the following statement are true or false :
Salt and water can be recovered from an aqueous salt solution by the process of evaporation.
Name the process which can be used to purify an impure sample of copper sulphate.
Fill in the following blanks with suitable words :
The separation of liquids by fractional distillation is based on the difference in their .....................
How will you separate iron pins from sand ?
How will you separate water from mustard oil ?
The technique which is used to separate particles of a solid suspended in a liquid quickly is called :
The correct increasing order of the boiling points of liquid oxygen, liquid argon and liquid nitrogen present in liquid air is :
The liquid air has three components X, Y and Z whose boiling points are : –186°C, –183°C and –196°C,
respectively. When liquid air is fed into a tall fractional distillation column from near its bottom and warmed
up slowly :
(a) Which component will be collected from near the bottom of the fraction distillation column ? Why ?
(b) Which component will be collected from the top part of the fractional distillation column ? Why ?
(c) Which component will be collected from the middle part of the fractional distillation column ? Why ?
(d) What could the component X, Y and Z be ?
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 ?
Atoms or groups of atoms having a charge are called ______.
Solid is an arrangement of particles ______.
Define the term matter.
