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It state that ,"in a pure chemical substance ,the elements are always present in definite proportion by mass ." It was given by J proust and is also know as law of definite proportion

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Smita Sharma 5 years, 10 months ago

Constant means having fixed proprtion by mass. For example : - G = 6.673 ( 10 )-11 . There are several examples of constants. The value of constant remains the same. G is said to be gravitational constant. The mass of the earth is 5.97 ( 10 * 10 * 10 * ..... 24 times. ) , remains the same.

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Amrutha S 5 years, 10 months ago

A chemical compound is always made up of the same elements combined together in the same fixed proportion by mass.

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Define the structure of neuron.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Aryan Kumar 5 years, 10 months ago

Although neurons look complicated, their design is actually quite simple. The neuron is broken up into two major regions: A region for receiving and processing incoming information from other cells A region for conducting and transmitting information to other cells The type of information that is received, processed and transmitted by a neuron depends on its location in the nervous system. For example, neurons located in the occipital lobe process visual information, whereas neurons in the motor pathways process and transmit information that controls the movement of muscles. However, regardless of the type of information, all neurons have the same basic anatomical structure.

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How is work and energy related to each other?

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

Rajneesh Payal 5 years, 10 months ago

WORK IS DONE WHEN FORCE IS APPLIED WHEN FORCE IS APPLIED AUTOMATICALLY WE USED ENERGY.

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Ishita Lamba 5 years, 10 months ago

Energy is the ability to do work

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Manish Yadav Yadav 5 years, 10 months ago

Energy the ability to do work

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Explain the following: (a) An object increases its energy when raised through a height. (b) Energy is neither created nor destroyed then from where dowe get energy. (c) When we push the wall, the wall does not move and no work is done.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Ashlesh Kumar 5 years, 10 months ago

The answer for c- accordind to science Work/work done -force ×diplacement Work will only be done when an object is displaced and force is applied to it. W =f ×s That is why when we push a wall by applying force, we actually do not do work as the wall /object is not diaplaced and remains stationary..

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Ashlesh Kumar 5 years, 10 months ago

The answer for A- this phenomenon is potential energy at height when the object is raised to a height then kinetic energy is 0 and potential energy (assumption/ let's keep it) will be 800 and it will remain same till the object reaches it's upmost point then the kinetic energy will start increasing and the potential energy will decrease uniformly. You should also note that the sum of kinetic energy +potential energy will remain to be same. For more doubts please refer ncert activities

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A solution is made by dissolving 50g sugar in 250g of water.calculate the concentration of this solution in mass%

Posted by Tinaben Parmar 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

Rajneesh Payal 5 years, 10 months ago

16.6666

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Asma Shah 5 years, 10 months ago

Mass%=mass of solute/mass of solution×100 =50/50+250×100 =50/300×100 =16.666...

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Rohit Maurya 5 years, 10 months ago

Solution:- total solution =50+250=300. We know mass%= mass of solute /mass of solution.×100. 50/300×100=16.6666......

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What is pinna

Posted by Ramchand Babu Ps 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Rajneesh Payal 5 years, 10 months ago

Outer part ear

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Ishita Lamba 5 years, 10 months ago

Outer ear

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What is the atomicity of Ca(OH)2?

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

Rajneesh Payal 5 years, 10 months ago

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Asifa Naaz 5 years, 10 months ago

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Ishita Lamba 5 years, 10 months ago

Calcium hydroxide

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Write the formula for Aluminium Chloride.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

Rajneesh Payal 5 years, 10 months ago

Alcl3

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Ishita Lamba 5 years, 10 months ago

AlCl³

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Ã.P.W.B.Đ ⚡ 5 years, 10 months ago

AlCl3

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ANSWER

4. Find the number of moles in 7g of Na.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Ishita Lamba 5 years, 10 months ago

.3181....mole

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Rohit Maurya 5 years, 10 months ago

Number of mole = given mass/mass of 1 na. =7/22 = .3181........ mole

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ANSWER

. Explain the difference of O2 and 2O.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rohit Maurya 5 years, 10 months ago

O2 only for o but 2o for all elements.

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ANSWER

1. Explain the molecular mass of C2H5OH.

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rohit Maurya 5 years, 10 months ago

Carbon =12 ×2=24 Hydrogen =1×50+1=51 Then, 24+51=76.

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ANSWER

. Explain the law of constant proportion

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rohit Maurya 5 years, 10 months ago

In any compound element always present in definite proportion

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ANSWER

how to separate different mixtures of air,???????

Posted by Kavya Rathour 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Ishita Lamba 5 years, 10 months ago

Fractional distillation

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Arpita Hurria 5 years, 10 months ago

By fractional distillation

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difference between centrifugal and cetripetal

Posted by Arun Kushwaha 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Aryan Kumar 5 years, 10 months ago

Centrifugal and Centripetal forces may both be called a force, but one of them is really not a force at all. There is a relationship between the two forces, however. Centrifugal results from inertia, the tendency of an object to resist any change in its state of motion or when it is at rest, though it is technically not a force. Centrifugal describes an object as it flies outward along a curved path, away from the center of the curve. Often times it is called an "apparent force", mainly because it feels like a force. On the other hand, centripetal force is a true force that will offset the centrifugal "force" stopping the motion of the object from its flying outward, keeping it in motion instead at a consistent speed along the curved or circular path. Centripetal is the force that prevents the moon from floating out of the Earth's orbit. Centrifugal force was defined in 1659 by Christiaan Hygens, and Isaac Newton defined centripetal force 25 years later in 1684. A major difference between centrifugal and centripetal force is the direction of each. Centrifugal takes place along the radius of the circle from the center out towards the object. For centripetal, it is the opposite, taking place also along the radius of the circle, but from the object in towards the center. Basically, both are defined by their frame of reference, centrifugal from the center towards the outside, centripetal from the outside towards the inside or center. A couple examples of each type of force may help one see the difference between the two. A centrifugal force example is the mud flying off of a spinning tire, or children being pushed out on a merry-go-round. The force the children feel is centrifugal force pushing them outward.

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Best aap for class 9

Posted by 45516111? 46 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rajneesh Payal 5 years, 10 months ago

Cbse guide and brainly app

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Why air is called mixture

Posted by Umang Tripathi 5 years, 10 months ago

CBSE > Class 09 > Science

4 answers

Rajneesh Payal 5 years, 10 months ago

Becsuse many gas is mix with another fas

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Rohit Maurya 5 years, 10 months ago

Mixture is a cantain more then two components

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45516111? 46 5 years, 10 months ago

Because it contains many particles of dust and mixture of many gases like nitrogen

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Ankita Kushwaha 5 years, 10 months ago

It contains many substances such as dust,smole etc.

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ANSWER

What do you mean by axon

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Ashlesh Kumar 5 years, 10 months ago

The nerve ending of an nerve cell . It has short parts which are called axons Please refer ncert

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Why should preventive measures and biological control methods be preferred for protecting crops?

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

0 answers

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What is fertilization

Posted by Prem Kr Roy 5 years, 10 months ago

CBSE > Class 09 > Science

0 answers

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Ch 7

Posted by Kushank Singh 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Ankita Kushwaha 5 years, 10 months ago

This chapter is about the varieties of plants and animals The great diversity of plants and animals have been divided so that they van be easier to study Whittaker has proposed the five kingdom of classification that is 1.monera 2.protista 3.fungi 4.plantae 5.animalia In plantae those are further divided into five categories that is 1.gymnosperms 2.angiosperms 3.thallophyta 4.bryophyta 5.pteridophyta In animalia these are divided into ten categories that is 1. Porifera(lowest organisms) 2.coelenterata(live in water) 3.platyhelminthes(these are triploblastic) 4.nematoda(body flattened) 5.annelida(true body cavity) 6.arthropoda(largest group of animals) 7.mollusca(cavity is reduced) 8.echinodermata(spiny mammals skin) 9.protochordata(new body designs) 10.verterbata(used for muscle attachment)

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Why cooler makes more cooling in a dry and hot day

Posted by Tinaben Parmar 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rohit Maurya 5 years, 10 months ago

Because evaporation directly proposnal to heat

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ANSWER

We cannot distroy momentum then why everyone says to conserve it?

Posted by Asifa Naaz 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Asifa Naaz 5 years, 10 months ago

Koi bta dijiye

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Universal Facts 5 years, 10 months ago

I also dont know

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ANSWER

Explain about mole concept Please

Posted by Ankita Kushwaha 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

Kavya Rathour 5 years, 10 months ago

1 mole is equal to 6.023× 10 ^23 . TIS NUMBER IS CALED AVAGDRO NUMBER . IT IS REPRESENTED BY "N" . IF ANYONE SAYS THAT OBJECT HAS 1MOLE OF OXYGEN ATOMS THEN IT MEANT THAT 6.023×10^24 ATOMS ARE PRESENT IN IT . THERE ARE MANY FORMULAS FOR FINDING MOLE . HERE I GIVE YOU OE... NO OF MOLE = GIVEN MASS / MOLECULAR MASS .

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Rohit Maurya 5 years, 10 months ago

The number of particales (aroms,molecules or ions) present in 1 mole of any substance is fixed.

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Ankita Kushwaha 5 years, 10 months ago

Plz tell me the answer

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ANSWER

Explain the law of conservation of mass

Posted by Aryan Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

3 answers

45516111? 46 5 years, 10 months ago

It can not be created nor destroyed

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45516111? 46 5 years, 10 months ago

It gives reactant= product

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Ankita Kushwaha 5 years, 10 months ago

It is total mass of products is equal to total mass of reactants It can neither be destroyed nor created in a chemical combination It can be changed from one form to another but not can be created nor destroyed

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please give me clash of clans id and password

Posted by Satyam King 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Shourya Jain 5 years, 10 months ago

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Akarsh Anshu 5 years, 10 months ago

???

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*****

Posted by Satyam King 5 years, 10 months ago

CBSE > Class 09 > Science

1 answers

Rohit Maurya 5 years, 10 months ago

#######

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what is ***** please give me ans for girls

Posted by Satyam King 5 years, 10 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Why does the water kept in an earthen pot become cool in summer

Posted by Roshni Prajapati 5 years, 10 months ago

CBSE > Class 09 > Science

4 answers

Rohit Maurya 5 years, 10 months ago

The membrane of pot has minute hole where fill water when heat act on surface then fill water evaporat and provide cooling effect in the pot

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Shourya Jain 5 years, 10 months ago

Water becomes cool because evaporation from the minute holes of the earthern pot takes place that causes cooling effect inside the pot..

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Sunaina Sahu 5 years, 10 months ago

Because of evaporation

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Roshni Prajapati 5 years, 10 months ago

Please answer me

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ANSWER

Laws of chemical combination

Posted by Suraj Kumar 5 years, 10 months ago

CBSE > Class 09 > Science

2 answers

Rohit Maurya 5 years, 10 months ago

There are two law . The laws of chemical combination founder is .l. levoisier . (1)laws of conservation of mass :- Mass neither be created or destroyed any chemical reactions. (2) laws of constant propertion :- in a compound the elements are always present in definite proportion.

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45516111? 46 5 years, 10 months ago

Like H2o mass have 1:8

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