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Diffrence between mixture and compound

Posted by Nancy Sati 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Compound	Mixture
Compound are substances which are formed by chemically combining two or more elements.	Mixtures are substances that are formed by physically mixing two or more substances.
Compounds are three types which are covalent compounds, metallic compounds and ionic compounds.	Mixtures are mainly of two types i.e. homogenous mixtures and heterogeneous mixtures.
Compounds fall under pure substances.	Mixtures fall under impure substances.
The chemical composition of compounds is always fixed.	A mixture can have a variable composition of the substances forming it.

ANSWER

Why lysosomes are known as suicide bags?

Posted by Tanishka Rautela 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Lysosomes are cellular organelles that contain digestive enzymes that break down waste materials, foreign material and cellular debris. Lysosomes are capable of digesting nucleic acid, polysaccharides, fats, and proteins. Along with them lysosomes also digest or damage its own cells by its own enzymes, which lead to cell death. This process is called as autolysis. Hence lysosomes are also called as suicide bags .

ANSWER

What is peunomonoultramicroscopicsilicovolcanyosis

Posted by Pari Sharma 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

How many palents are in our solar system

Posted by Lotan Singh 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Kumkum Sarswat 7 years, 2 months ago

Eight mercury Venus earth Mars Jupiter Saturn Uranus Neptune

Bhawna Katyayan 7 years, 2 months ago

8

Ritik Tevathiya 7 years, 2 months ago

8

Pari Sharma 7 years, 2 months ago

8

ANSWER

Volume if spere whose radius is 7 cm

Posted by Harshal Mali 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Harshal Mali 7 years, 1 month ago

..

Yogita Ingle 7 years, 2 months ago

The space occupied by an object solid body is called the volume of the particular object solid body volume is always measured in cubic unit.

A sphere is a three dimensional figure which is made up of all points in the space which lie at a constant distance from a fixed point called the centre of the sphere and a constant distance is called its radius.

Radius of the sphere(r) = 7 cm

Volume of the sphere = 4/3πr³

= (4/3 × 22/7 × 7 × 7 × 7)

= (88 × 7 × 49)/3 × 7

= 4312/3 = 1437 ⅓
= 1437 ⅓ cm³

ANSWER

Formula of calcium nitrate

Posted by Ritik Tevathiya 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Calcium nitrate, also called Norgessalpeter (Norwegian saltpeter), is an inorganic compound with the formula Ca(NO₃)₂. This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate. It is mainly used as a component in fertilizers but has other applications.

ANSWER

Write all formulas of physics chapter chapterwise

Posted by Prashant Bhati 7 years, 2 months ago

CBSE > Class 09 > Science

5 answers

Kumkum Sarswat 7 years, 2 months ago

Chapter 12 Speed = wavelength / time Speed = wavelength x frequency

Kumkum Sarswat 7 years, 2 months ago

Chapter 11 W = f x s Or W = mg x s Kinetic energy = 1/2 mv square Potential energy = mgh P = W / t

Kumkum Sarswat 7 years, 2 months ago

Chapter 10 F = G M x m / d square g = G M / d square W = m x g Pressure = force or thrust / area Relative density = density of a substance / density of water

Kumkum Sarswat 7 years, 2 months ago

Chapter 9 Momentum = mass x velocity Or p = mv F = ma Conservation of momentum mAuA + mBuB = mAvA + mBvB

Kumkum Sarswat 7 years, 2 months ago

Chapter 8 Speed = distance / time Velocity = displacement / time a = v - u / t Equations of motion v = u + at s = ut + 1/2 at square 2as = v square - u square

ANSWER

Bhor atom modal

Posted by Himanshu Singh 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Neils Bohr, a Danish physicist, in 1913 proposed model of atom which rectified the problems left by Rutherford’s Model. He proposed that

Electrons revolve round the nucleus in a fixed orbit.
He called these orbits as ‘stationary orbit’.
Each stationary orbit is associated with fixed amount of energy, thus electrons do not radiate energy as long as they keep on revolving around the nucleus in fixed orbit.

ANSWER

can anyone explain me the thomson model and his model drawback

Posted by Sangita???? Ankita 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Akanksha Kumari? 7 years, 2 months ago

J.J Thomson proposed the 1st model of an atom. According to Thomson 's atomic model , electrons are widely distributed in the positively charged sphere. He compared it with Christmas pudding by stating that the electrons are like the dry fruits which are embedded in the pudding which is a positively charged sphere . He almost compared it with a watermelon . He concluded that the red edible part of it is the positively charged sphere in which electrons as seeds are embedded. This atomic model gave us the following conclusions: 1. Electrons and protons are equal in magnitude. So, an atom is electrically neutral as a whole . 2. Electrons are present in the positively charged sphere. Drawbacks of model: 1. He didn't described the proper arrangements of Electrons in an atom. I hope this will help you ??

Palak ?? 7 years, 2 months ago

He also said that the whole atom was electrically nuteral

Palak ?? 7 years, 2 months ago

Thomson's model proposed that structure of an atom was just like a watermelon in which a positively charged sphere consistent negatively charged electrons embedded in it it was not considered write because it was not able to explain the for the experiments carried out by other scientist

.Yogitha . Dhanaji 7 years, 2 months ago

आणि मग ते दोघं एकमेकांना चांगले ओळखत होते की काय नीट समजून घेण्यासाठी फक्त एकच जण जाऊ शकत नाही म्हणून जगातल्या सगळ्या गोष्टी करायच्या आहेत हे समजून घेणे अत्यंत आवश्यक आहे की माझे मराठी उत्तम

ANSWER

Who discovered the cell ?

Posted by Sumitkumar Jadhav 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Kumkum Sarswat 7 years, 2 months ago

Robert hook in 1665 while examining cork

Rishita Singh 7 years, 2 months ago

Robert Hook

Sangita???? Ankita 7 years, 2 months ago

robert hook in 1665

Sumitkumar Jadhav 7 years, 2 months ago

Robert hook

ANSWER

A stone is allowed to fall from a height of 80m. Find its position after 4s.

Posted by Dheeraj Upraity 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Find out the number of potassium if the atomic number is 19 and the mass number is 39

Posted by Piyush Rastogi 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Palak ?? 7 years, 2 months ago

What number....?

ANSWER

Iow of conservation of mass

Posted by Arjun Ramesh 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Akanksha Kumari? 7 years, 2 months ago

Law of conservation of mass was proposed by Antoine lavosier. According to this law, mass of reactants is equal to the total mass of products. It means that mass can neither be created nor be destroyed.

Saurabh Bisht 7 years, 2 months ago

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Saurabh Bisht 7 years, 2 months ago

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Saurabh Bisht 7 years, 2 months ago

Law of conversation of mass means that the mass can neither be created nor destroyed in any chemical reactions... I hope this will help you If this help you then touch on thanks

ANSWER

1)Rutherford told that any charged particles in circular motion undergoes acceleration and good radiate energy 2)Borh told that while revolving In discrete orbits the electrons do not radiate energy From the both cases 1)Rutherford told good radiate energy 2)Borh told that do not radiate energy What does it mean ?❓❔❔❔❔

Posted by Akhila P Nair 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Palak ?? 7 years, 2 months ago

Hey!u r getting that wrong.. Ruther Ford said that the electrons revolve around the nucleus in Orbit then there was a contradiction between him and the other scientist they said that if something is revolving around then it will undergo acceleration and will radiate energy . They said that if we tie a Bob to a string and move it in a circular direction then after some time it will come to rest at the centre and same will happen with the structure of atom the electrons will lose energy and come at the centre and collide with the nucleus which will result in unstability of an atom but then bohar told that when when electrons revolve around the nucleus they do not lose their energy they are somehow and exceptional case.....hope that will help u

ANSWER

What is great revolution ?

Posted by Harsh Dubey 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Aditya Kumar 7 years, 2 months ago

High production or yield of food grain is called green revolution

Aditya Kumar 7 years, 2 months ago

I think harsh meant by green revolution

Palak ?? 7 years, 2 months ago

A revolution which is great??

ANSWER

What is your sounf

Posted by Jatin Malik 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Name the three characteristics of sound

Posted by Satya Yadav 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Kumkum Sarswat 7 years, 2 months ago

Frequency Amplitude Speed

ANSWER

Mention any one method of incorporation desirable characters into a crop variety

Posted by Ar Gamer 7 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Kumkum Sarswat 7 years, 2 months ago

I also not understand the question

Sayahnika Mishra 7 years, 2 months ago

??

Simran Kaur 7 years, 2 months ago

Not understood question

Ar Gamer 7 years, 2 months ago

Hahaa

ANSWER

What is electron, protone nutrone

Posted by Prabhat Baliyan 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Kumkum Sarswat 7 years, 2 months ago

Electron is negatively charged particle proton is positively charged particle and neutrons are neutral

Simran Kaur 7 years, 2 months ago

These all are sub atomic particles. Electrons have negative charge , protons have positive charge , neutrons have no charge means they are neutral

ANSWER

State relation between commercial unit of energy and joules

Posted by Kamal Mittal 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Kumkum Sarswat 7 years, 2 months ago

1 kW h = 1 kW x 1 h = 1000 W x 3600 s = 3600000 1 kW h = 3.6 x 10 raised to the power 6

Khushi Boora 7 years, 2 months ago

1 kwh= 3.6 ×10^6 J

ANSWER

Protista is uni cellular

Posted by Badshah Raghav 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Bhawna Katyayan 7 years, 2 months ago

Yessssd

Kumkum Sarswat 7 years, 2 months ago

Yes ??????

Aanchal Jaiswal 7 years, 2 months ago

Member of this phyllum are unicellular

ANSWER

What is arthapoda

Posted by Ishika Juneja 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

How is AIDS caused??

Posted by Cheshta Bhati 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Arushi Sharma 7 years, 2 months ago

Aids is caused by HIV vrius HIV- Human Immuno deficiency Virus

Kumkum Sarswat 7 years, 2 months ago

HIV virus

Shourya Yadav 7 years, 2 months ago

By Hiv virus

ANSWER

Whether the velocity of an object will increase or decrease if direction is changed

Posted by Simran Kaur 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Simran Kaur 7 years, 2 months ago

Not understood

Cheshta Bhati 7 years, 2 months ago

It depends upon the situation whether the speed is decreased or increased during change of direction. Change in direction shows change in velocity as it is a vector quantity.

ANSWER

Why uniform circular motion is called accelerated motion?

Posted by Simran Kaur 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Khushi Boora 7 years, 2 months ago

Because in this motion direction changes every time. Distance remain same but displacement changes so it is called accelerated motion.

ANSWER

Calculate 60g of carbon and 60g of magnesium elements have a molar ratio 2:1 [atomic mass of c=12u,mg=24u].

Posted by Sandhya Mahanty 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Anil Kumar 7 years, 2 months ago

Molar =12 24 24/12=2:1

Gaurav Seth 7 years, 2 months ago

The molar mass of carbon=12
the molar mass of mg=24

therefore,the mass of both are same .

molar ratio = molar mass of mg/molar mass of
carbon
=24/12
=2/1
that is, 2:1 ratio

ANSWER

Explain the term compressibility of gases? ?

Posted by Neha Panwar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 7 years, 2 months ago

The molecules are further apart and there is more space between the different molecules, which
makes the gas more compressible. Due to the high compressibility, the large
volumes of the gas can be compressed and can easily be transported.

The examples are:

The LPG (liquefied
petroleum gas) cylinder that we use in our homes for cooking.

The CNG (compressed
natural gas) that we use in our vehicles.

ANSWER

Name the physical quantity whose SI unit is hertz

Posted by Kashif Ansari 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Kumkum Sarswat 7 years, 2 months ago

It is frequency ??????

Atharva Pandey 5 years, 11 months ago

Frequency

Aayush Gadiya 7 years, 2 months ago

Frequency

ANSWER

Number of molecucules in 100g of NH3 is more than 100g of N2

Posted by Sandhya Mahanty 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Gaurav Seth 7 years, 2 months ago

M,Molar mass of NH₃=14+(1×3)=17
m,Given mass=100 g
n,number of moles=m/M=100/17
n=N/N₀
N=n×N₀=(100/17)×6.022×10²³
=3.55×10²⁴

M,Molar mass of N₂=14×2=28
m,Given mass=100 g
n,number of moles=m/M=100/28
n=N/N₀
N=n×N₀
(100/28)×6.022×10²³=2.15×10²⁴

∴Number of molecules in 100 g of NH3 is more than 100 g of N2.

Gaurav Seth 7 years, 2 months ago

M,Molar mass of NH₃=14+(1×3)=17
m,Given mass=100 g
n,number of moles=m/M=100/17
n=N/N₀
N=n×N₀=(100/17)×6.022×10²³
=3.55×10²⁴

ANSWER

Why do we snake and turtle in the same class

Posted by Shiwang Singh 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Cheshta Bhati 7 years, 2 months ago

Because they both are reptiles means both creep/crawl Snake is exceptional case in reptiles as it doesn't have limbs (foots )

Khushi Boora 7 years, 2 months ago

✓ Body is covered by scales. ✓ Skin is dry, rough and without glands. ✓ Have three chambered heart. ✓ Lateral sense organs are absent.

ANSWER

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