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What is ionic bond give example

Posted by Ayan Jais 5 years, 3 months ago

CBSE > Class 10 > Science

4 answers

Shruti Janghu 5 years, 3 months ago

For example NaCl , CaCl2

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Shruti Janghu 5 years, 3 months ago

Ionic bond is a chemical bond bw 2 atoms which involves transfer of electron. The ionic bond always takes place bw metals and nonmetals. For example NaCl , NaOH.

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Anubhav Shukla 5 years, 3 months ago

Ionic bonding is the complete transfer of valence electron(s) between atoms. Ionic bond will take place between metals and non-metals. for example NaCl sodium electronic configuration is 2,8,1 and electronic configuration of Cl is 2,8,7 sodium is a metal that means it will donate its one electron to become stable and the property of metal is also to loss electron to get positive charge and on the other hand Cl is non metal and the property of non metal is to gain electron so Cl will gain one electron from Na to become stable and Na will become stable by lossing one electron and Cl will become stable by gaining one electron so through this way they will form a IONIC BOND. similarly u can get more examples but remember to take one metal who has to loss 1 ,2,3, electrons and the same u have to take the non metal that will gain 1,2,3 electrons and therefore ionic bond is the bond in which metal and non metals are involved.

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Priya ✧*｡٩(๑˙╰╯˙๑)و✧*｡ 5 years, 3 months ago

Ionic bond is a kind of chemical bond which involves an electrostatic attraction between two oppositely charged ions because of the complete transfer of valence electrons between them.Examples of Ionic Bonds: 1. Sodium chloride - NaCl - table salt 2. Calcium chloride - CaCl2 – rock salt 3. Sodium hydroxide - NaOH - Lye used in soap

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ANSWER

Function of lungs

Posted by Anshuman Omm 5 years, 3 months ago

CBSE > Class 10 > Science

0 answers

ANSWER

Calculate the area of cross section of a wire if its length is 1.0m its resistance is 23ohm

Posted by Anukriti Sharma 5 years, 3 months ago

CBSE > Class 10 > Science

1 answers

Priya ✧*｡٩(๑˙╰╯˙๑)و✧*｡ 5 years, 3 months ago

I = 1.0 m R = 23 ohm p = 1.84 × 10-6 ohm – meter We have R = P. I/A 23 = 1.84 × 10-6 × 1/A A = (1.84 × 10-6 )/23 = 0.08 × 10-6 m2 = 8 × 10-8 m2

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Mention any 3 methods adopted by plants to minimise the transpiration rate

Posted by Jacinth Samuel Nok 5 years, 3 months ago

CBSE > Class 10 > Science

1 answers

Yogita Ingle 5 years, 3 months ago

Plants reduce water loss by closing their stomata, developing thick cuticles, or by possessing leaf hairs to increase the boundary layer.

i) The stomata are the primary control mechanisms that plants use to reduce water loss and they are able to do so quickly. Stomata are sensitive to the environmental cues that trigger the stomata to open or close. Some plant species have stomata on both sides of the leaf while others have stomata on the lower leaf surface to minimize water loss. Special cells called guard cells control each pore’s opening or closing. When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease. Stomata are the only way plants can control transpiration rates in the short-term.

ii) The boundary layer is a thin layer of still air hugging the surface of the leaf. This layer of air is not moving. For transpiration to occur, water vapor leaving the stomata must diffuse through this motionless layer to reach the atmosphere where the water vapor will be removed by moving air. The larger the boundary layer, the slower the rates of transpiration. Plants can alter the size of their boundary layers around leaves through a variety of structural features. Leaves that possess many hairs or pubescence will have larger boundary layers; the hairs serve as mini-wind breaks by increasing the layer of still air around the leaf surface and slowing transpiration rates. Some plants possess stomata that are sunken into the leaf surface, dramatically increasing the boundary layer and slowing transpiration. Boundary layers increase as leaf size increases, reducing rates of transpiration as well.

iii) The cuticle is the waxy layer present on all above-ground tissue of a plant and serves as a barrier to water movement out of a leaf. Because the cuticle is made of wax, it is very hydrophobic; therefore, water does not move through it very easily. The thicker the cuticle layer on a leaf surface, the slower the transpiration rate. Cuticle thickness varies widely among plant species. In general, plants from hot, dry climates have thicker cuticles than plants from cool, moist climates. In addition, leaves that develop under direct sunlight will have much thicker cuticles than leaves that develop under shade conditions. Sun leaves have much thicker cuticles than shade leaves causing slower rates of transpiration.

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Class 10 hereditary and evolution notes

Posted by Mananpreet Singh 5 years, 3 months ago

CBSE > Class 10 > Science

1 answers

Aman Gupta 5 years, 3 months ago

Why should a magnesium ribbon be cleard before burning in air?

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ANSWER

Which of the following is an example for conventional sources of energy. a.wind energy b.bio mass c.wood d.solar energy

Posted by Harish Ar 5 years, 3 months ago

CBSE > Class 10 > Science

1 answers

Meghna Thapar 4 years, 11 months ago

Conventional energy sources includes oil, gas and coal. These conventional sources are usually fossil fuels. Their use leads to increased greenhouse gas emissions and other environmental damage.These sources of energy are also called non renewable sources. These sources of energy are in limited quantity except hydro-electric power. These include commercial (coal, petroleum, electricity etc..) and non-commercial (fire wood, straw, dried dung etc..)

Cutting	A small part of a plant which is removed by making a cut with a sharp knife is called cutting. Example - rose.
Layering	In this method, a branch of the plant is pulled towards the ground and a part of it is covered with moist soil leaving the tip of the branch exposed above the ground. After some time, new roots develop from the part of the branch buried in the soil. The branch is then cut off from the parent plant. The part of the plant which has developed roots grows to become new plant. Example - Jasmine plant.
Grafting	Grafting is the method in which cut stems of two different plants are joined together in such a way that the two stems join and grow as a single plant. The cut stem of a plant having roots is called stock whereas the cut stem of another plant without roots is called scion.

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