Amorphus solids :-
Category Archives: science
Why the solids are rigid?
The solids have strong interparticulate forces which bind the particles so close that they can only oscillate about their mean position only.
Learn periodic table in just 25 minutes in punjabi .
you can learn the complete chapter in just 25 minutes.
what are the types of rectifiers ?
There are two types of rectifier:
Why do we need a rectifier?
The electric power is generated,transmitted and distributed in the form of alternating current because alternating voltage can be transmitted easily up or down but electronic devices operates best on direct current and they requires direct current supply. We can only convert a.c. into d.c. with rectifiers.
What is a rectifier?
A rectifier is a P-N junction diode.
Define Rectification
Rectification :- A process in which an alternating current or voltage is converted into direct current or voltage with the help of electrical device named as rectifier.
Benzene is soluble in toluene but not in water . Why ?
Like dissolves like. Toluene is a non polar solvent and benzene is also non polar in nature, so it dissolves in toluene. But on the other hand water is a non polar solvent and due to this benzene do not dissolve in it.
How is it that alcohol and water are miscible in all proportions ?
solution
Calculate the mass of urea (NH2CONH2) required in making 2.5kg of 0.25 molal aqueous solution .
What type of stoichiometric defect is shown by (i) ZnS (ii)AgBr.
(i) ZnS have large difference in the size of their ions and due to this it shows Frankel defect. (ii) AgBr shows Schottky defect and Frankel defect.
Which of the following lattice has the highest packing efficiency? (i) simple cubic (ii) bodycentred (iii) hexagonal close packing.
Packing efficiency of all these kind of arrangements is given as follows. (i) Simple cubic :- Its packing efficiency is 52% . (ii) Body centred cubic :- Its packing efficiency is 68%. (iii) Hexagonal close packing:- Its packing efficiency is 74% . Conclusion :- From the above data we can conclude that hexagonal close packedContinue reading “Which of the following lattice has the highest packing efficiency? (i) simple cubic (ii) bodycentred (iii) hexagonal close packing.”
What is the two dimensional co-ordination number of a molecule in square close packed layer ?
In a square close packed two dimensional layer , four other particles touch one particle. Thus its coordination number is 4 .
What type of defect can arise when a solid is heated ? Which physical property is affected by it and in what way ?
On heating the crystal lattice, some of the lattice particles gain enough energy that they jump from their lattice points. Due this the crystal appears coloured and its density decreases.
Give the siginificance of lattice point .
These are the points in a crystal lattice that can be occupied by an atom, ion or a molecule.
Why are solids rigid ?
In case of solids the particles have strong forces of attractions between them . Due to this they can not move or change their positions. Due to this they are rigid.
What is myopia near sightedness class 10th cbse pseb board classes
This is a type of eye defect Near sightedness or Myopia is a defect of eye in which the objects present near can be seen clearly but the far ibjects can not be seen by the person suffering from this disease. It can arise due to the following reasons :- 1. Increased length of eyeContinue reading “What is myopia near sightedness class 10th cbse pseb board classes”
What is rancidity ? Why the packets of chips and fries are flushed or filled with nitrogen gas while packing?
It is the foul smell produced by the oxidation of oils and nuts. Mostly the bitter taste of peanut and food made by frying is due to rancidity . Normally the oily substances which are not covered properly , react with the oxygen of air and get oxidised thus give a foul smell. Removal ofContinue reading “What is rancidity ? Why the packets of chips and fries are flushed or filled with nitrogen gas while packing?”
Why should a magnesium ribbon should be cleaned before burning in air?
Magnesium is a reactive metal, it reacts with the oxygen of air and forms magnesium oxide. Magnesium oxide makes a layer on the upper surface of the metal. Which makes it difficult for the magnesium to get burnt and give characteristic flame. By using sandpaper we can remove its upper layer for proper combustion reactionContinue reading “Why should a magnesium ribbon should be cleaned before burning in air?”
The electrons that gain enthalpy for metals is positive and negative for non metals. Also, if metals are bigger in size than non metals then, how can electrons gain enthalpy is inversely proportional to the atomic size?
The answer is simple, like you are hungry you can pay more to get the food than that of the person who is less hungry, Similarily here the non metals want electrons thus they spend the energy more , or they release the energy. By this they lose the energy. So smaller is the sizeContinue reading “The electrons that gain enthalpy for metals is positive and negative for non metals. Also, if metals are bigger in size than non metals then, how can electrons gain enthalpy is inversely proportional to the atomic size?”
ਪਾਠ 10
page number 181 1 ਅਵਤਲ ਦਰਪਣ ਦੇ ਮੁੱਖ ਫੋਕਸ ਦੀ ਪ੍ਰੀਭਾਸ਼ਾ ਦਿਓ ।ਉੱਤਰ :- ਅਵਤਲ ਦਰਪਣ ਦਾ ਮੁੱਖ ਫੋਕਸ ਉਹ ਬਿੰਦੂ ਹੁੰਦਾ ਹੈ ਜਿਸ ਉੱਤੇ ਦਰਪਣ ਤੇ ਟਕਰਾਉਣ ਤੋਂ ਬਾਅਦ ਪ੍ਰਕਾਸ਼ ਦੀਆਂ ਕਿਰਨਾਂ ਮਿਲਦੀਆਂ ਹਨ ਜਾਂ ਮਿਲਦੀਆਂ ਹੋਈਆਂ ਪ੍ਰਤੀਤ ਹੁੰਦੀਆਂ ਹਨ 2 ਇਕ ਗੋਲਾਕਾਰ ਦਰਪਣ ਦਾ ਵਕਰਤਾ ਅਰਧ ਵਿਆਸ 20 ਸੈਂਟੀਮੀਟਰ ਹੈ ਉਸ ਦੀ ਫੋਕਸContinue reading “ਪਾਠ 10”
ਅਵਤਲ ਦਰਪਣ ਦੇ ਮੁੱਖ ਫੋਕਸ ਦੀ ਪ੍ਰੀਭਾਸ਼ਾ ਦਿਓ ।
ਉੱਤਰ :- ਅਵਤਲ ਦਰਪਣ ਦਾ ਮੁੱਖ ਫੋਕਸ ਉਹ ਬਿੰਦੂ ਹੁੰਦਾ ਹੈ ਜਿਸ ਉੱਤੇ ਦਰਪਣ ਤੇ ਟਕਰਾਉਣ ਤੋਂ ਬਾਅਦ ਪ੍ਰਕਾਸ਼ ਦੀਆਂ ਕਿਰਨਾਂ ਮਿਲਦੀਆਂ ਹਨ ਜਾਂ ਮਿਲਦੀਆਂ ਹੋਈਆਂ ਪ੍ਰਤੀਤ ਹੁੰਦੀਆਂ ਹਨ ।