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Write any two differences between pure substance and mixture

Posted by Ketul Jadav 4 years, 2 months ago

1 answers

Yogita Ingle 4 years, 2 months ago

Pure Substances	Mixtures
It cannot be broken down or separated into new products.	It can be separated using different separation methods.
Constant physical and chemical properties.	Mixtures have varying physical and chemical properties.
Pure substance consists of a single element.	A mixture is a combination of two substances or elements.

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ANSWER

Wt is homogeneous

Posted by Shravya S Rao 4 years, 2 months ago

CBSE > Class 09 > Science

5 answers

Shweta Singh 4 years, 2 months ago

Homogeneous is the type of mixture in which the composition is balanced

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Shree Kushwaha 4 years, 2 months ago

Non homogeneous system, like those obtained by group C in activity 2.2 in which solids are dispersed in liquid ,are called suspension

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Arpana Bharti 4 years, 2 months ago

Same type of element

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Bangtan Army Forever 4 years, 2 months ago

This is a type of mixture made up of parts that all are of the same type

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Tanisha Agarwal 4 years, 2 months ago

What is suspension

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ANSWER

Alka was making tea in a kettle. Suddenly she felt intense heat from the puff of steam gushing out of the spout of the kettle. She wondered whether the temperature of the steam was higher than that of the water boiling in the kettle. Comment.

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 2 months ago

The boiling point of water is 100°C. The temperature of boiling water does not rise instead of continuous supply of heat, as the extra heat is supplied to the water is used to turn water into steam. Hence, steam has a lot of latent heat which can cause severe burn. That’s why Alka felt intense heat from the puff of steam gushing out of the spout of the kettle.

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ANSWER

What is cell sap?

Posted by Siddhantika Chaturvedi 4 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Shree Kushwaha 4 years, 2 months ago

Liquid content in the vacuole of plants cells is called cell sap

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Shreyansh Jain 4 years, 2 months ago

Liquid inside the vacuole is also called cell sap

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Yogita Ingle 4 years, 2 months ago

Liquid content in the vacuoles of plant cell is called cell sap. The cell sap contains sugars, amino acid, proteins, minerals and metabolic wastes

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ANSWER

What determines the state of a substance

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 2 months ago

1. Temperature and pressure determine the state of a substance. A change in temperature or pressure will result in the change of state of the substance.

2. Strength of the bonds between the atoms. The strength of bonds depends on the temperature or the amount of energy possessed by the matter.

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ANSWER

After morning exercise you feel cold why?

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Shani Baiswade 4 years, 2 months ago

Because after exercise we sweat a lot due to evaporation and we know that evaporation causes cooling

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Yogita Ingle 4 years, 2 months ago

Because after exercise we sweat a lot and because of that latent heat takes the heat of our body and evaporates to form vapour. and as we know that evaporation causes cooling.

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ANSWER

A substance has no mass. Can we consider it as matter?

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Akshat Holland Minettee 4 years, 2 months ago

No because anything that has mass and occupies space is only call matter.

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Shweta Singh 4 years, 2 months ago

First of all it is not possible because everything in world has their own mass. But otherwise it happens then it will not come in the category of matter

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Yogita Ingle 4 years, 2 months ago

Matter is defined as a substance or entity which has mass and occupy some space. So if a substance has no mass we cannot regard it as matter.

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ANSWER

Suppose you want to convert a gas into a liquid. Which two methods can you apply

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Suzanne Smitha 4 years, 2 months ago

1.condensation 2.increase temperature and decrease pressure

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Yogita Ingle 4 years, 2 months ago

In order to convert a gas into a liquid, following methods can be chosen.

• Condensation or liquefying of the gases which is the process of converting gases into liquids.

• When you increase the temperature and decrease the pressure, the gaseous state is converted into liquid state on this impact.

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ANSWER

Very short questions Which will have more density – a solid or a liquid give reason

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Bhagyesh Kame 4 years, 2 months ago

Density is mass/volume. Since the solid have a compressed state it will have less volume resulting in more density. Where as in fluid the volume will be depending upon the shape of the container in which it is stored.

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Anamika Gangurde 4 years, 2 months ago

Solid because liquid are tend to flow, they take the shape of the container on which they are kept. They do not have a definite shape, but solids molecules are very to each other ,and they Attract each other ( attract each molecules)toward them. Solid have a definite shape

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Bangtan Army Forever 4 years, 2 months ago

Solid has more density because in solid, particles are more tightly packed with each other we take great interparticle force as compared to liquid which particles are less tightly packed with each other than solid .

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ANSWER

Four examples of connective tissue in humans

Posted by Swarali Kadam 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Aarti Balu 4 years, 2 months ago

Four examples of connective tissues are tendon, cartilage, bone and Areolar.

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Yogita Ingle 4 years, 2 months ago

Connective tissues, as the name implies, support and connect different tissues and organs of the body. They are widely distributed in every part of the body. They originate from the mesoderm (the middle germinal layer of the embryo)
It includes fibrous tissues, fat, cartilage, bone, bone marrow, and blood. As the name implies, connective tissues often bind other organs together, hold organs in place, cushion them, and fill space.

Read more: <a href="http://www.biologyreference.com/Ce-Co/Connective-Tissue.html#ixzz6SXpqSyPk">http://www.biologyreference.com/Ce-Co/Connective-Tissue.html#ixzz6SXpqSyPk</a>

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ANSWER

Factor which is inversely proportional to the rate of evaporation

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Bhagyesh Kame 4 years, 2 months ago

The factor inversely proportional to rate of evaporation is humidity. As humidity increases the rate of evaporation decrease. This is why it takes longer time for clothes to dry in rainy season as humidity is high in rainy season.

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Yogita Ingle 4 years, 2 months ago

Factors That Affect the Evaporation

Temperature: As the temperature increases, the rate of evaporation also increases. Temperature and rate of evaporation are proportional to each other
Surface area: As the surface area increases, the rate of evaporation increases. The surface area and rate of evaporation are proportional to each other.
Humidity: The rate of evaporation decreases with an increase in humidity. Humidity and the rate of evaporation are inversely proportional to each other.
Wind speed: Increase in wind speed results in increased evaporation. Wind speed and rate of evaporation are proportional to each other.

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ANSWER

What is the boiling point of water on Kelvin scale

Posted by Parth Dariyani 4 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Shree Kushwaha 4 years, 2 months ago

373.15 k

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Divya Gupta 4 years, 2 months ago

373.15k

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Piyushi Sharma 4 years, 2 months ago

373.15K

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Yogita Ingle 4 years, 2 months ago

As boiling point of water in celcius scale is 100 degree celcius.
So as per formula K=273.15+c . As value of c is 100 degree celcius so its value be 373.15 K.

The boiling point of water in kelvin scale is 373.15 K.

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ANSWER

What is dehyrogen monoxide

Posted by Dakshal Chauhan 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 2 months ago

Dihydrogen monoxide (DHMO) is the scientific name for water, though it is almost never used. But the name is technically correct for water. It is a colourless, odourless, tasteless chemical compound and the major component of acid rain which is also known as hydroxyl acid. It also contributed to the greenhouse effect. It accelerates corrosion of many metals. Water is covalent compound, but dihydrogen monoxide is ionic so both are not the same.

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A body started from a height of 10m with initial velocity 0. find out kinetic energy of body with out the formula (m=20 kg)

Posted by Dhanush M 4 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is the formula of angular velocity and momentum

Posted by Vedansh Bajaj 4 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Ekta Ekta 4 years, 2 months ago

Above answer are sufficient

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Yogita Ingle 4 years, 2 months ago

Definition: The degree to which a body rotates, gives its angular momentum. It is defined as the product of the moment of inertia “I” and the angular velocity “ω”

L =Iω

Angular momentum in terms of Linear momentum can be written as

$L=r\times p$

where,

r = length vector

p = linear momentum

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Ritika Sharma 4 years, 2 months ago

Angular velocity=wr(w means omega) Momentum=mv

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ANSWER

Define diffrentiation

Posted by Rehyaa Arjun 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 2 months ago

In reference to biology, Differentiation is a process in which cells, tissues, organs acquire certain characteristics and features which makes them specialized in the function they perform.

For example, differentiation of meristem into specialized cells and tissues like plants and stems.

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ANSWER

A body travels with a uniform speed of 8m/s for 10s and then with a speed of 12m/s for 15s. Calculate its average speed.

Posted by Priyanshu Parate 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Aarti Balu 4 years, 2 months ago

Isn't 0.8m/s the right answer?

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Ritika Sharma 4 years, 2 months ago

Speed=total distance/total time =10×8 + 12×15/10+15 =260/25 =10.4 m/s

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ANSWER

Difference between RERand SER?

Posted by Jiya Pasare 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 4 years, 2 months ago

ROUGH ENDOPLASMIC RETICULUM	SMOOTH ENDOPLASMIC RETICULUM
These are rough at surface and are associated with ribosomes.	These are smooth at surface and are associated with Golgi bodies.
These are responsible for the synthesis of proteins and enzymes.	These are responsible for the synthesis of glycogen, lipids etc.
These provide structural framework for the cell.	These take part in the synthesis of fats in adipose cells.
These also act as channels for quick transport.	These can also detoxify drugs and some poisons.
These help in the synthesis of membranes.	These help in the formation of rhodopsin from vitamin A.

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ANSWER

A body starts from rest and undergoes a uniform acceleration of 5m/s for 6 seconds. Calculate its final velocity and the distance travelled.

Posted by Priyanshu Parate 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Dakshal Chauhan 4 years, 2 months ago

30 m/s (Final velocity)

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Ritika Sharma 4 years, 2 months ago

v=u+at =0+5×6(u=0 as body starts from rest) =30m/s(final velocity) v²-u²=2as v²-u²/2a=s (30)²-(0)²/2×5= s 900/10=s 90m=s

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ANSWER

Draw a diagram of internal structure of chloroplast along with the explanation of chloroplast.

Posted by Jiya Pasare 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 4 years, 2 months ago

The chloroplast has an inner and outer membrane with an empty intermediate space in between. Inside the chloroplast are stacks of thylakoids, called grana, as well as stroma, the dense fluid inside of the chloroplast. These thylakoids contain the chlorophyll that is necessary for the plant to go through photosynthesis. The structure of the chloroplast is adapted to the function it performs: Thylakoids – flattened discs have a small internal volume to maximise hydrogen gradient upon proton accumulation. ... Photosystems – pigments organised into photosystems in thylakoid membrane to maximise light absorption.

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What are the two components of biosphere

Posted by Vedika Bhatt 4 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Vedika Bhatt 4 years, 2 months ago

Thanks

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Gaurav Seth 4 years, 2 months ago

The region on earth comprising of both biotic and abiotic components is called as biosphere.

1. Biotic components include all the living organisms. Living organisms comprise of plants, animals and microorganisms.

2. Abiotic components include air, water and the soil. Biotic components interact with all the abiotic components such as air, water and soil to sustain their life.

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ANSWER

the rate of evaporation depends upon the surface area exposed to the atmosphere the temperature the humidity and the wind speed

Posted by Murtiram Joshi 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 4 years, 2 months ago

rate of evaporationdoes depend on surface area because if the surface area is more then their will be more contact to the environment so the bonds between the molecules would take lesser time to break but it also depends on nature of liquid,wind speed, humidity and temperature

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ANSWER

Posted by Rahul?⚾ Dhaka 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Farzaan Khan 4 years, 2 months ago

Bhai questions puchna hai toh puchna.

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ANSWER

give some example of deposition process

Posted by Diyanshu Baghel 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 4 years, 2 months ago

Water vapor to ice - Water vapor transforms directly into ice without becoming a liquid, a process that often occurs on windows during the winter months.
Physical vapor to film - Thin layers of material known as "film" are deposited onto a surface using a vaporized form of the film.

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ANSWER

What does the path of an object look like when it is in uniform motion?

Posted by Shourya Rajput 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Gaurav Seth 4 years, 2 months ago

q : What does the path of an object look like when it is in uniform motion?

A N S W E R :

An object is said to be in uniform motion if it moves with constant velocity i.e. the object must be moving in a straight line.

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ANSWER

Why does space looks blue during day fromnp earth if it is because of reflection then image need screen to form but space is not any screen?

Posted by Harsh Vardhan 4 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Hanshika (Honey) 4 years, 2 months ago

I think because of Tyndall effect

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ANSWER

Where are protien synthesized inside the cell?

Posted by Siddhi Vinayak 4 years, 2 months ago

CBSE > Class 09 > Science

5 answers

Shree Kushwaha 4 years, 2 months ago

Ribosome

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Aarti Balu 4 years, 2 months ago

In the ribosome

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Ritika Sharma 4 years, 2 months ago

Ribosomes

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Divya Gupta 4 years, 2 months ago

RNA is present in Ribosomes play a significant role in synthesizesing protein

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Shabd Kumar 4 years, 2 months ago

In ribosomes

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ANSWER

What are atoms ....defination please

Posted by Debasmita Deb 4 years, 2 months ago

CBSE > Class 09 > Science

4 answers

Sumana Banerjee 4 years, 2 months ago

An atom is the smallest constituent unit of ordinary matter that constitutes a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics – as if they were billiard balls, for example – is not possible due to quantum effects. Current atomic models use quantum principles to better explain and predict this behavior.

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Rd Campus 4 years, 2 months ago

Atoms are defined as “the basic building blocks of matter”. It is the smallest constituent unit of matter that posses the properties of the chemical element. Atoms don’t exist independently, instead, they form ions and molecules which further combine in large numbers to form matter that we see, feel and touch. Atoms are much too small to be seen; hence experiments to find out their structure and behavior have to be conducted with large numbers of them. From the results of these experiments we may attempt to construct a hypothetical model of an atom that behaves like the true atom.

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Vallabh Pawar 4 years, 2 months ago

The spreading of fragrance of incense stick from a corner to the whole room indicates that particles of matter keep moving from higher to lower concentration.

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Siddhi Vinayak 4 years, 2 months ago

Atoms is the smallest components of an element, characterized by a sharing of the chemical properties of the elements and a nucleus with neutrons protons and electrons.

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ANSWER

Which of the following component added to water followed by vigorous stirring form a true solution, suspension or a collid -soap,femous sulphate,calcium carbonate,sodium chloride,starch and wheat flour.

Posted by Abhishek Aryan 4 years, 2 months ago

CBSE > Class 09 > Science