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Physical change : Change in which no new substance formed and that is reversible Chemical change : Change in which new substance formed and that is irreversible

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Explain human digestive system

Posted by N Jaswanth Sri Sai Njaswanth 8 years, 4 months ago

CBSE > Class 07 > Science

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WHat is soater?

Posted by Rajat Kaushal 8 years, 4 months ago

CBSE > Class 07 > Science

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What is photosenthesis

Posted by Tushal Kumar 8 years, 4 months ago

CBSE > Class 07 > Science

2 answers

Mansi Maurya 8 years, 4 months ago

And water also

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Udit Shah 8 years, 4 months ago

Photosynthesis is the process by which Green plants make the food with the help of chlorophyll in presence of carbon dioxide and sunlight.

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Working of thermos flask

Posted by Ayan Shin 8 years, 4 months ago

CBSE > Class 07 > Science

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Syamala Devi Nukella 8 years, 4 months ago

A vacuum flask, or thermos, does not allow heat transfer by any of the three ways that heat can travel. The silver coating on the inner bottle prevents heat transfer by radiation, and the vacuum between its double wall prevents heat moving by convection.

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What is a instruments that measures the cyclone speed

Posted by Mukesh Tandan 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Angel Bansal 8 years, 4 months ago

Anemometer

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Describe the process of photosynthesis

Posted by Somi Notani 8 years, 4 months ago

CBSE > Class 07 > Science

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What is climate

Posted by Harmeet Singh 8 years, 4 months ago

CBSE > Class 07 > Science

3 answers

Anjali Sharma 8 years, 4 months ago

Climate is defined as the sum of weather of a particular place for along period of time like for years which repeats every year.

it depends upon

altitude of the place
latitude
distance form the sea
the landform of the area etc.

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Nasifa Faliha 8 years, 4 months ago

Average weather condition of a region

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Harmeet Singh 8 years, 4 months ago

What is climate

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What do you mean by saprotrophs

Posted by Prabhjot Kaur 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Shreya Jha 8 years, 4 months ago

Organisms that derive nutrition from dead and decaying matters they are called saprotrophs

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What is the physical change

Posted by Nithish Waran 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Angel Bansal 8 years, 4 months ago

A change that is reversible and are temporary changes

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What is precipitation

Posted by Niranjana Tamilarasan 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Mavuri Pardhu 8 years, 4 months ago

The falling of moisture on the ground in the form of rainfall, snow, sleet, and hailstones

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What is symbiosis

Posted by Sk Deepak 8 years, 4 months ago

CBSE > Class 07 > Science

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Mansi Maurya 8 years, 4 months ago

The living together of two different species of plants as if they are parts of the same plant and help each other in obtainin food is called symbiosis.

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Short note on soil erosion

Posted by Aryan Meana 8 years, 4 months ago

CBSE > Class 07 > Science

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Amar Kumar 8 years, 4 months ago

Soil erosion is defined as the wearing away of topsoil. Topsoil is the top layer of soil and is the most fertile because it contains the most organic, nutrient-rich materials. One of the main causes of soil erosion is water erosion, which is the loss of topsoil due to water.Rainfall and the surface runoff which may result from rainfall, produces four main types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.

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Science

Posted by Mamatha Moger 8 years, 4 months ago

CBSE > Class 07 > Science

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How do organisms need to take food

Posted by Sanjay Sharma 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Mansi Maurya 8 years, 4 months ago

Without energy it will die soon...

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describe the process of digestion in ruminants

Posted by Sakshi Aggarwal 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Amar Kumar 8 years, 4 months ago

Ruminant Artiodactyl (including cattle, deer, and their relatives) are unable to digest plant material directly, because they lack enzymes to break down cellulose in the cell walls. Digestion in ruminants occurs sequentially in a four-chambered stomach. Plant material is initially taken into the Rumen, where it is processed mechanically and exposed to bacteria then can break down cellulose .The Reticulum allows the animal to regurgitate & reprocess particulate matter ("chew its cud"). More finely-divided food is then passed to the Omasum, for further mechanical processing. The mass is finally passed to the true stomach, the Abomasum, where the digestive enzyme lysozyme breaks down the bacteria so as to release nutrients.

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formula of calcium nirtate

Posted by Nimisha Mohan 8 years, 4 months ago

CBSE > Class 07 > Science

2 answers

Nimisha Mohan 8 years, 4 months ago

thankyou u so much

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Amar Kumar 8 years, 4 months ago

Calcium nitrate, also called Norgessalpeter (Norwegian saltpeter), is an inorganic compound with the formula Ca(NO₃)₂.

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Acid react with Base to form what

Posted by Keshav Garg 8 years, 4 months ago

CBSE > Class 07 > Science

2 answers

Badshahon Ka Badshah 8 years, 4 months ago

Salt and water by evolution of heat

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Keshav Garg 8 years, 4 months ago

Acid react with Base to form salt and water

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Why does a turmeric stain turn red if washed with soap?

Posted by Anushri Tomar 8 years, 4 months ago

CBSE > Class 07 > Science

3 answers

Mansi Maurya 8 years, 4 months ago

It is a reaction proves that turmeric and soap is bases....

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Jessy D 8 years, 4 months ago

Soap is base.Turmeric is a indicator which turns bases brick red.So, a turmeric stain in a shirt turns red if washed with soap

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Badshahon Ka Badshah 8 years, 4 months ago

Because it is a base

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What is neutralition and Write there application of it in daily life

Posted by Ayush Ramola 8 years, 4 months ago

CBSE > Class 07 > Science

3 answers

Badshahon Ka Badshah 8 years, 4 months ago

Reaction between acid and a base is called neutralisation 1.when we suffer from indigestion we take baking soda 2.soil is treated by quick lime 3.when an ant bites it injects formic acid so to neutralize it's effect we will rub calamine lotion on our body

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Amar Kumar 8 years, 4 months ago

Neutralisation is a chemical reaction in which an acid and a base react quantitatively with each other.

To treat acidic and basic soil
To treat acidic effluents in industry.
To treat gastric patients and to prevent tooth decay

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Raveesh Yadav 8 years, 4 months ago

Reaction of acid and base is known as neutralisation reaction. During acidity we use antacid to neutralise the effect of acid.

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What unusal qualities of wool make it a very useful fibre..??? 3marks question

Posted by Rangam Trivedi 8 years, 4 months ago

CBSE > Class 07 > Science

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What is knitting?

Posted by Vivek Gupta 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Amar Kumar 8 years, 4 months ago

Knitting is a method by which yarn is manipulated to create a textile or fabric for use in many types of garments. Knitting creates multiple loops of yarn, called stitches, in a line or tube. Knitting has multiple active stitches on the needle at one time.

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Differenciate between percolation rate and absorption rate

Posted by Nistha Saha 8 years, 4 months ago

CBSE > Class 07 > Science

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What is the vakency of berylium

Posted by Krrish Tyagi 8 years, 4 months ago

CBSE > Class 07 > Science

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Difference between acidic and basic?

Posted by Abinaya Sree 8 years, 4 months ago

CBSE > Class 07 > Science

2 answers

Badshahon Ka Badshah 8 years, 4 months ago

The substances which are sour in taste are called acids. The substances which are bitter in taste are called as base

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Anjali Sharma 8 years, 4 months ago

Acids

those substance which are sour in taste
They breakdown to give H⁺ ion in water
they are not soapy to touch
they changes blue litmus to red
for examples lemon, HCl, tamarind.

bases

those substances which are bitter in taste
they breakdown to give OH^-ion in water
they are soapy to touch
they changes red litmus to blue
for examples soap, NaOH etc

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Distinguish between physical and chemical change

Posted by Amit Raaj 8 years, 4 months ago

CBSE > Class 07 > Science

2 answers

Abhishek Rai 8 years, 4 months ago

Key Differences Between Physical Change and Chemical Change

The points given below discusses significant differences between physical change and chemical change

A change in which the molecules are rearranged, but their internal composition remains same is called Physical Change. A process in which the substance transforms into a new substance, having a different chemical composition, it is known as Chemical Change.
Some common examples of physical change vaporisation, condensation, freezing/melting/boiling of water. On the contrary, the examples of chemical change are combustion, metabolism, cooking of egg, etc.
Physical change is a temporary; they are easily reversible. As against this, the chemical change is permanent in nature, i.e. they cannot be reversed, even by reversing conditions.
In the physical change, only the form of the substance is changed, but no new product is formed. On the other hand, when there is a chemical reaction, a completely different product is formed, whose properties are completely different from that of the reacting substances.
In a physical change, the original matter can be recovered, by simple physical methods. As opposed, in chemical change the original matter no longer exist, and so it cannot be recovered.
In the physical change, change in the physical attributes of the substance is observed, such as shape, size, appearance, texture, odour, density and so on. Conversely, chemical change involves the change in chemical properties of the substance, i.e. change in its chemical nature.
In the physical change, no or very little amount of energy is absorbed or given out as heat, light or sound energy. Unlike chemical change, wherein enormous energy is absorbed or given out as heat, light or sound energy.

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Yash Mundra 8 years, 4 months ago

The main difference is Physical change is reversible while Chemical change is irreversible

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Good conductor of heat

Posted by Imran Mann 8 years, 4 months ago

CBSE > Class 07 > Science

3 answers

Rangam Trivedi 8 years, 4 months ago

The material that allows heay to pass through them easily are called good conductors of heat. For example- aluminium and copper

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Anjali Sharma 8 years, 4 months ago

Those element or simply we can say metals which allow the heat to pass through them easily are known as good conductor of heat. For example Iron and many other metals

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Tanisha Jain 8 years, 4 months ago

Example - iron

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What is osmosis

Posted by Harjot Kaur 8 years, 4 months ago

CBSE > Class 07 > Science

1 answers

Rutuparna Panda 8 years, 4 months ago

Osmosis is the scientific process of transferring fluid between molecules. When molecules move in and out of a cell to achieve the same concentration of something, like salt, on both sides, then osmosis is happening.

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Why Sandy soil is light aerated and dry

Posted by Ajay Singh 8 years, 4 months ago

CBSE > Class 07 > Science