Mechanical digestion :- In this type of digestion the food is broken down into simple particles in mechanical way , like chewing in mouth by teeth and churning of food in stomach by the muscular movements of the smooth muscles of stomach walls. Chemical digestion :- In this type of digestion the complex molecules of
In case of ionic solids the opposite ions balance the charge of each other. The amount of cations and anions is mostly same in case of charge. But when we add a cation with higher charge , the cation can replace the other cations in lattice and can create vacancy because to balance the charge,
These type of semiconductors have excess electrons present in the lattice that are responsible for the conduction. These are formed when the group 14 elements like Silicon are doped with group 15 elements like P and As. The group 14 elements have 4 valence electrons and group 15 elements have 5 valence electrons . One
When we add extra metal to the lattice, it provide extra electrons to the lattice and the anions of the lattice leave their lattice points . These vacant sites are occupied by the electrons. And the free electron can easily absorb energy and can jump to higher level. As these energy transitions are in visible
(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.
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 packed
In a square close packed two dimensional layer , four other particles touch one particle. Thus its coordination number is 4 .
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.
These are the points in a crystal lattice that can be occupied by an atom, ion or a molecule.
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.
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 eye
We can calculate the number of electrons in a given shell by using a simple formula as given below. 2n² Where “n” is the number of shell. For example In case of K shell , n=1 So the number of electrons = 2n² = 2 x 1² =2 So in K shell we have 2
In case of Hexagonal unit cell we have two sides equal , and two angles equal to 90 degrees(right angles) but the third angle is of 120 degrees. a = b ≠ c, and similarly α = β = 90 ̊, ɣ = 120 ̊ But in case of monoclinic unit cell we have unequal sides but
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 of
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 reaction
Actually it is a process in which the green plants synthesize their food from the water and carbondioxide in the presence of sunlight and chloroplast. The following reaction depicts the chemical change during photosynthesis.
Today we are in a modern era where a lot modernisation has took place. In the field of metals various metals are mixed to get the desired properties. The alloys are used in transportations , machines , telecommunications and a lot more. Basically the alloy is the homogenous mixture two or more metals and some
The atomic Size is an important property that governs various behaviours of an atom or an element, like valency , electronegativity and metallic character. when we move from left to right the nuclear charge increases at every increase of atomic number. Due to increase in nuclear charge the electrons are attracted towards nucleus with more
Yes it is a chemical change as it involves the formation of ash and releases heat. Which can not be reversed to get fuel. In a chemical change the change of properties take place . For example we can write on paper and can fold it ,but if we burn it we get ash and
Density depends upon the number of particles in a unit area. So it doesn’t matter what kind of particles are used. So it is a physical property.
No, dissolving is a physical process, provided that the substances which are being mixed should not react with each other.
Naming the chemical compounds take a lot of practice and memorising some rules just click here .
This is true that a strong acid HCl is formed in our stomach , but it does not harm the internal tissues or organs. The acid is formed for two major reasons. To carry out the digestion especially the enzyme pepsin requires acidic medium for the proper functioning . The acid acts as a first