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Lewis dot structures reflect the electronic structures of the elements, including how the electrons are paired. Lewis structures are a useful way to summarize certain information about bonding and may be thought of as “electron bookkeeping”. In Lewis dot structures each dot represents an electron. A pair of dots between chemical symbols for atoms represents a bond.

Lewis Structure of CO₂

The central atom of this molecule is carbon.
Oxygen contains 6 valence electrons which form 2 lone pairs. Since it is bonded to only one carbon atom, it must form a double bond.
Carbon contains four valence electrons, resulting in zero lone pairs. Therefore, it is doubly bonded to each oxygen atom.

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ANSWER

Define molecular formula with an appropriate example?

Posted by All In One 4 years, 5 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 5 months ago

Molecular formula is a chemical formula of a compound existing as descrete molecules that gives total no. of each element in a molecule.
Fpr example: Molecular formula of oxygen is O₂.

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Why photosynthesis proces considered as endothermic reaction?

Posted by Naina Choudhary. 4 years, 5 months ago

CBSE > Class 10 > Science

5 answers

उपेंद्र वर्मा 4 years, 5 months ago

Because a certain amount of energy is abosrbed during this process, that's why it is known as endothermic reaction

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All In One 4 years, 5 months ago

In photosynthesis heat is absorbed from sunlight, that's why it is known as endothermic reaction.

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Akhya Sahay 4 years, 5 months ago

B coz it absorbs light energy from sun.

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Nishika Sharma 4 years, 5 months ago

It is endothermic because it can take place in the presence of sunlight and energy is absorbs through the green pigment chlorophyll. Reaction..... C6 H12 6O2 --------- 6CO2+ 6H2O+energy

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Art Of Writing 4 years, 5 months ago

Yes, photosynthesis is a endothermic reaction because it can't occur without energy (from sun) . The light energy absorb by a green pigment.

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ANSWER

how show that plants are live and don't alive?

Posted by Art Of Writing 4 years, 5 months ago

CBSE > Class 10 > Science

2 answers

Bipin Kumar 4 years, 5 months ago

If their leaves unable to proceed photosynthesis.

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Adithya Dev A 4 years, 5 months ago

Take a leaf and do starch test (blue black --->alive). Close it using a bell jar with a hole (water vapour ---->alive).

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ANSWER

Our board exams should not be cancelled as it is subject of our future we students do not fear from Corona. Who is with me?

Posted by Bishwadip Raj 4 years, 5 months ago

CBSE > Class 10 > Science

5 answers

Bipin Kumar 4 years, 5 months ago

No one with you

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Saurabh Singh 4 years, 5 months ago

I am with you but I am not with you ?

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Abhishek Kumar 4 years, 5 months ago

My area is hotspot

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Abhishek Kumar 4 years, 5 months ago

I m not with you

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Aastha Choudhary 4 years, 5 months ago

I am with you!!!

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ANSWER

what is name of baking soda

Posted by Nitin Sangwan 4 years, 5 months ago

CBSE > Class 10 > Science

5 answers

All In One 4 years, 5 months ago

NaHCO3

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Nishika Sharma 4 years, 5 months ago

Sodium hydrogen carbonate

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Vani Vashisht 4 years, 5 months ago

The chemical name is sodium hydrogen carbonate

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Bishwadip Raj 4 years, 5 months ago

Sodium Hydrogen Carbonate

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Uday Bhan 4 years, 5 months ago

why do we store silver chloride in dark coloured bottles

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ANSWER

What is environment pollution?

Posted by Nisa Saini 4 years, 5 months ago

CBSE > Class 10 > Science

5 answers

Ekta Yadav 4 years, 5 months ago

Hlo nisi .. it's eku ...where are you from? ?

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Daksh . 4 years, 5 months ago

Thank

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Adithya Dev A 4 years, 5 months ago

Contamination of environment by disappropriately high amounts of undesirable substances which directly or indirectly bring harm to the environment as a whole is known as ENVIRONMENT POLLUTION. It is a human made disaster which may even lead to global ecological crises like global warming and ozone layer depletion.

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Nisa Saini 4 years, 5 months ago

Thank u

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Ricky Tomar 4 years, 5 months ago

That is formed by people

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ANSWER

Why are life process important?

Posted by Om Prakash Baral 4 years, 5 months ago

CBSE > Class 10 > Science

4 answers

Saurabh Singh 4 years, 5 months ago

To sustain life

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Akhya Sahay 4 years, 5 months ago

It is important as it supports all the metabolic activities. It is also responsible for growth and repair.

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Divyank Panwar 4 years, 5 months ago

It helps in reproduction

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Mayand Saini 4 years, 5 months ago

Because they are important for sustaining life

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ANSWER

What is Egestion?

Posted by Sakshi Shah 4 years, 5 months ago

CBSE > Class 10 > Science

4 answers

Rupesh Kumar Yadav 4 years, 4 months ago

The process of removal of waste products is called Egestion

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Nisa Saini 4 years, 5 months ago

When a beam of light is incident on a polished surface and sent back in same medium this phenomenon is called reflection of ligjt

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Yashika Verma 4 years, 5 months ago

What is reflection of light?

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Krish Agrawal 4 years, 5 months ago

The removal of undigested or unusual materials

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ANSWER

Posted by Gagandeep Singh 4 years, 5 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 5 months ago

D)21.3cm

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ANSWER

An electric heater having resistance equal to 5omh is connected to electric source if it produces 180 joule of heat in one second find the potential difference across the electric heater.

Posted by Shubh Pathak 4 years, 5 months ago

CBSE > Class 10 > Science

1 answers

Shubh Madheshiya 4 years, 5 months ago

R=5ohm W=180j P=180j/s P=V^2/R 180=VxV/5 V=√900 V=30v

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ANSWER

You have been provided with a freshly plucked leaf of rhoeo or lily . what will you do to obtain a transperent leaf peel?

Posted by Riya Verma 4 years, 5 months ago

CBSE > Class 10 > Science

4 answers

Ekta Yadav 4 years, 5 months ago

Hi riu ... it's your bff eku...oyee kal school aayegi kya ?? ???

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Adithya Dev A 4 years, 5 months ago

Sorry, it is not peel (last), it is leaf.

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Adithya Dev A 4 years, 5 months ago

Take a small needle and then, with utmost focus, slowly procure a very thin layer of leaf peel from the margins of the peel.

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Aakash Anand 4 years, 5 months ago

I don't know tell me.... Uu ?

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ANSWER

Identyfy the refrevtive index of a transparante medium what is its unit ? Which has a higher refrection index glass or water

Posted by Mohmmed Arslan 4 years, 5 months ago

CBSE > Class 10 > Science

4 answers

Ankit Poonia 4 years, 5 months ago

How is oxygen and carbon dioxide transported in human being

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Aakash Anand 4 years, 5 months ago

bhai Tum question Mein spelling mistake bahut jyada Ki Hai

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Aakash Anand 4 years, 5 months ago

Refractive index of a transparent medium is the ratio of speed of light in vaccum to speed of light in medium......,.................... ................ Refractive index has no units.... .... Aakash anand?

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Aakash Anand 4 years, 5 months ago

Higher reflection index is glass

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ANSWER

Differentiate between budding and fission

Posted by Raushan Raj 4 years, 5 months ago

CBSE > Class 10 > Science

2 answers

Adithya Dev A 4 years, 5 months ago

BUDDING = found in unicellular and multicellular organisms. A small cytoplasmic outgrowth arises in body of organism known as BUD due to repeated division of cells ---> detach to form new offspring. Eg :- Hydra, yeast, etc....... FISSION = found only in unicellular organisms. Parent body divides into two or more daughter cells. Eg :- amoeba, leishmania, paramoecium, etc.

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Bipin Kumar 4 years, 5 months ago

Budding is a asexual mode of reproduction in which new organism is formed by breaking down of outgrowth from it's body parts but I'm case of fission organism is formed when nucleus is divided.

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ANSWER

Explain two methods to determine the age of fossils? *please, explain in a way I can understand.

Posted by Rahul Kumar Jha 4 years, 5 months ago

CBSE > Class 10 > Science

1 answers

Adithya Dev A 4 years, 5 months ago

1) Depth of position. 2) Hardness.

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ANSWER

Biggest cell in living human body

Posted by Anisha Kumari 4 years, 5 months ago

CBSE > Class 10 > Science

5 answers

Anisha Kumari 4 years, 5 months ago

What is female?

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Mani Dhillon 4 years, 5 months ago

Ovum

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Aakash Anand 4 years, 5 months ago

Ovum and sperm

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Oav Papadahandi 4 years, 5 months ago

It's ✔??ravi

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Ravi Kushwaha 4 years, 5 months ago

The largest cell is ovum in the human body. The ovum also called egg cell is the reproductive cell in the female body. Ovum is 20 times bigger than the sperm cells and has a diameter of about 0.1 mm.

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ANSWER

How does the electronic configuration of an atom relates to its position in the modern periodic table ?

Posted by Anu Keshri 4 years, 5 months ago

CBSE > Class 10 > Science

3 answers

All In One 4 years, 5 months ago

Because our modern periodic table is based on atomic no., So the no. Of electron present in outermost shell and atomic no. determine the position of element in periodic table.

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Aakash Anand 4 years, 5 months ago

Number of electron in the outer most shell.................. Aakash Anand ?

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Bipin Kumar 4 years, 5 months ago

I don't know sister tell me.. uu

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ANSWER

What are similarities between nephrons in kidney and alveoli in lungs? Answer should be brief bro and sis Must reply

Posted by Bipin Kumar 4 years, 5 months ago

CBSE > Class 10 > Science