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What is the chemical formulation of sodium chloride??

Posted by Deepanshu Dash 5 years, 1 month ago

4 answers

Sodium chloride, commonly known as salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g/mol respectively, 100 g of NaCl contains 39.34 g Na and 60.66 g Cl.

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Kashish Chauhan 5 years, 1 month ago

NaCl

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Sarthak Gupta 5 years, 1 month ago

Sodium Chloride is an ionic compound with the chemical formula NaCl. Sodium Chloride is also known as salt.

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Yogita Ingle 5 years, 1 month ago

Sodium Chloride is an ionic compound with the chemical formula NaCl. Sodium Chloride is also known as salt.

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What are meristematic cell? Write the characters also

Posted by Hanshika Shina 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 1 month ago

Carl Wilhelm von Nägeli coined the term “meristem.” Meristematic tissue contains undifferentiated cells, which are the building blocks of the specialized plant structures.

Meristematic tissues contain living cells with varied shapes. They possess a large nucleus devoid of the vacuole. The cells have no intercellular space. The zone where these cells exist is known as meristem.

Characteristics of meristematic tissues:

1. They are made up of immature cells.

2. They have the capability to differentiate into any cell.

3. They are living and thin walled.

4. They are diploid in nature and show mitotic division.

5. The cells of meristematic tissues are rich in cytoplasm.

6. They do not contain reserve food materials, ER and plastids.

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The valency of neon is zero but that of sodium is one, why?

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Pramodsingh Rathore 5 years, 1 month ago

Because neon consist only 10 ectrons which estable its orbit so its valency is 0 But sodium consits 2 electrons in k orbit than 8 in L orbit than 1 in M orbit so it take away the 1 elctron in other metal so its valency is 1

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Kashish Chauhan 5 years, 1 month ago

because neon has all 8 electrons in the outermost shell which is balance So neon element doesn't need to share or take any electron from any other one so its valency is zero. whereas sodium has one an electron in outermost shell which is not properly balance by which sodium has to loose 1 electron from the outer most shell that's why the sodium has valency 1..... I hope it will benefit you buddy...

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Which type of plastids are more common in roots of the plant, leaves of the plants,flowers and fruits

Posted by Soumya Shrivas 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Sarthak Gupta 5 years, 1 month ago

(a) Roots of plant → contain leucoplast which are colourless plastids and act as storage of food. (b) Leaves of plant → contain green coloured chlorophyll for photosynthesis (c) Flowers and fruits → contain multicoloured chromoplast to attract pollinators

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Gaurav Seth 5 years, 1 month ago

Answer :

(a) Roots of plant → contain leucoplast which are colourless plastids and act as storage of food.
(b) Leaves of plant → contain green coloured chlorophyll for photosynthesis
(c) Flowers and fruits → contain multicoloured chromoplast to attract pollinators

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sodium chloride is called electrovalent compound but ammonia is called covalent compound, why?

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 1 month ago

sodium chloride has strong force of attraction between its molecules are stable

ammonia has force of attraction between its molecules and are stable
sodium chloride is called electrovalent compound because it is formed by transfer of electrons between atoms but ammonia is called covalent compound because it is form by sharing of electron theory between atom

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Atom are electrical neutral.justify the statement

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 1 month ago

Atoms are electrically neutral because they have equal numbers of protons (positively charged) and electrons (negatively charged). If an atom gains or loses one or more electrons, it becomes an ion. If it gains one or more electrons, it now carries a net negative charge, and is thus "anionic.

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Tell me the amount of solute and solvent present in 2% (by mass) of glucose solution

Posted by Arun Kumar 5 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

Tell little explaination about meristematic tissue??

Posted by Bhumija Bajpai 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Nishant Paliwal 5 years, 1 month ago

Meristematic tissue or meristems, as they are also called are tissues that have the ability to enlarge, stretch and differentiate into other types of cells as they mature. The cells of this tissue are generally young and immature, with the power of continuous division. Meristematic cells are all living cells.

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Kunal Singh 5 years, 1 month ago

Meristmatic tissues can growth. It have 3 types :- 1.) Apical tissue 2. Lateral tissue 3. Intercallary tissue 1. Apical tissue is responsible for the growth of top of plants and roots. 2. Lateral tissue is responsible for the growth of thickness (Lateral parts of plants) 3. Intercallary tissue is responsible for the growth b/w two nodes. Meristmatic tissue can be permanent tissue when it lost its capability to growth.

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What is dispersion mediam

Posted by Ankit Chauhan 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Nishant Paliwal 5 years, 1 month ago

dispersed medium consists of two media that do not mix. More specifically, it contains discrete elements of one medium which are dispersed in a continuous second medium. The two media can be of very different nature. In particular, they can be a gas, a liquid or a solid.

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Ash Greninja 5 years, 1 month ago

Dispersion Medium: The component in which the dispersed phase is suspended is known as the dispersing medium.

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What is a colloidal solution?What are the properties of a colloid?.

Posted by Sayantika Malobika 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

M D Vishaal Narayanan 5 years, 1 month ago

Shows tindall effect

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Gaurav Seth 5 years, 1 month ago

Colloids

A colloid is a kind of solution in which the size of solute particles is intermediate between those in true solutions and those in suspensions.
For Example: - Soap solution, Milk, Ink, Blood and solutions of synthetic detergents.

In a true solution, the solute particles are so small that they cannot scatter or reflect light rays falling on them.
In a colloidal solution (or colloid), the particles are big enough to scatter light.
- If a beam of light is put on a colloidal solution kept in a beaker in a dark room, the path of light beam is illuminated and becomes visible when seen from the side.
- The path of light beam becomes visible because colloidal particles are big enough to scatter light falling on them in all directions.

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Can anybody gives me the MCQs Questions of the chapter The fundamental unit of life.

Posted by Shine Rai 5 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

How solution,sol and suspension different from each other?

Posted by Disha Patil 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Mufeedha S 5 years, 1 month ago

solution is a homogeneous mixture whereas suspension is a heterogeneous mixture

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What is centrifugation. Explain with example

Posted by Roshan Chand 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Ash Greninja 5 years, 1 month ago

It is a method of separating the suspended particles of a substance from a liquid in which the mixture is rotated at high speed in a centrifuge. This method is useful in case the suspended particles in a liquid are too small too be retained by filter paper. Principle of Centrifugation: When a mixture is rotated very fast, the denser particles are forced to go to the bottom of the centrifuge and the lighter particles stay at the top. Applications of Centrifugation: Used in dairies to separate cream from milk. Used in washing machines to squeeze out water from wet clothes.

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Gaurav Seth 5 years, 1 month ago

Centrifugation.
Answer: Sometimes the solid particles in a liquid are very small and pass through a filter paper. For such particles the filtration technique cannot be used for separation. Such mixtures are separated by centrifugation. The principle is that the denser particles are forced to the bottom and the lighter particles stay at the top when spun rapidly.

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How does population impacts on diseases

Posted by Suba Shree 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Nishant Paliwal 5 years, 1 month ago

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An electron moving with a velocity of 5 × 10 4 ms -1 enters into a uniform electric field and acquires a uniform acceleration of 10 4 ms –2 in the direction of its initial motion.

Posted by Komal Tank 5 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

Atom are electrically neutral. justify the statement.

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Gaurav Seth 5 years, 1 month ago

A N S W E R
A t o m s is electrically neutral as the number of protons is equal to the number of electrons. Therefore the negative and positive charge cancels out.

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Kritika Saini Girn 5 years, 1 month ago

Hgll

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sodium atom cannot exist freely in nature but argon can.Give reason

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 1 month ago

On looking on Argon we will see it has a stable configuration [Ne] 3s2 3p6 completely filled p orbital so it doesn't need to lose or gain electrons, it is a noble gas .

on the other hand if we look at sodium configuration it is [Ne] 3s1 , there is a free electron in the outer shell so it lose it to become more stable so it always doesn't exist in free form , elements are searching for stability

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Explain different types of motion based upon acceleration of object

Posted by Sowparnika Ram 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Hisham Ichoo 5 years, 1 month ago

I eont no

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Sowparnika Ram 5 years, 1 month ago

Answer

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Explain meristamatic tissue with diagram

Posted by Rengavadivelammal .C 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Nishant Paliwal 5 years, 1 month ago

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sodium is called an element and water is called a compound, why?

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 5 years, 1 month ago

An element is regarded as pure because it is only composed of a single type of atom.

e.g. Sodium is only composed of ‘Na’ atoms

A compound contains two or more different types of atoms bonded together.

e.g. Water has 'H' and 'O' in a fixed ratio (2:1)

Sodium is monoatomic, and composed of a single element and is an element found on the periodic table of elements

Water is triatomic, consist of more than one element making it a compound.

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Sodium is called an element and water is called a compound ,why?

Posted by Sunita Sapkota 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Shehrebanu .... 5 years, 1 month ago

An element is regarded as pure because it is only composed of a single type of atom. e.g. Sodium is only composed of ‘Na’ atoms A compound contains two or more different types of atoms bonded together. e.g. Water has 'H' and 'O' in a fixed ratio (2:1) Sodium is monoatomic, and composed of a single element and is an element found on the periodic table of elements Water is triatomic, consist of more than one element making it a compound

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Define inertia. Write some examples

Posted by Chandrika A G 5 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Nishant Paliwal 5 years, 1 month ago

Inertia is the resistance of any physical object to any change in its velocity. This includes changes to the object's speed, or direction of motion. An aspect of this property is the tendency of objects to keep moving in a straight line at a constant speed, when no forces act upon them.

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Devashish Kumar 5 years, 1 month ago

The tendency of a body to oppose any change in its state of rest, or uniform motion is known as inertia Example--(1) When a bus suddenly start passengers fall in backward direction. (2) When a carpet is bitten with stick dust comes out.

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Dolly Singh 5 years, 1 month ago

If an object is in rest it tends to remain at rest and if an object is in motion it tends to be in motion .This property of an object is called it's inertia ...Example-- when we kick a football it flies away but when we kick a stone with equal force it hardly moves...

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Difference between sound and light waves

Posted by Kartavya Singh 5 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 5 years, 1 month ago

Sound waves

Light waves

1. They are longitudinal waves

2. They cannot travel through vacuum

3. Its speed in air is 330 m/s

1. They are transverse waves

2. They do not require medium to propagate

3. Its speed in air or vacuum is 3x108 m/s

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Amit Kumar 5 years, 1 month ago

Sound waves travel with compression or rear faction but light wave travel perpendicularly

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Describe various types of Epithelial tissue with diagram

Posted by Rengavadivelammal .C 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 1 month ago

It consists of cells which form membranes.
This membrane covers the body surface and the glands.
The covering or protective tissues in the animal body are epithelial tissues.
Epithelium covers most organs and cavities within the body.
It also forms a barrier to keep different body systems separate.
The skin, the lining of the mouth, the lining of blood vessels, lung alveoli and kidney tubules are all made of epithelial tissue.
The cells are tightly packed and form a continuous sheet.

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Explain the difference of connective tissue

Posted by Rengavadivelammal .C 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 5 years, 1 month ago

It protects and supports the body.
The cells are loosely spaced and embedded in an intercellular matrix.
The matrix may be jelly like, fluid, dense or rigid.
The nature of matrix differs in concordance with the function of the particular connective tissue.

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Explain simple tissue with diagram

Posted by Rengavadivelammal .C 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Janvi Tiwari 5 years, 1 month ago

A group of cells that are similar in structure and work together to achieve a particular function is called a tissue

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A boy is Walking Alone on a road with and velocity 1.5 km per hour take to cover the distance 820 metre Express the velocity in the metre per second find the time taken to cover distance 820 metre

Posted by Jeevitha R 5 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pratyush Pradyun Subrata 5 years, 1 month ago

To Express the velocity in m/see need to multiply 1000 to 1.5 and 1 hr=3600 sec.then divide both . 1500/3600 =0.41 To find time taken we can use the formulae . Velocity =total displacement/total time. Total displacement =820 m V=0.41 m/s Total time =displacement/velocity. Time =820/0.41 Time =2000 sec.

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What will be the Mass of 10moles of phosphoric acid

Posted by Shubham Pandey 5 years, 1 month ago

CBSE > Class 09 > Science