Karan roll no30

Why the solid are not compressible but gas can compress easily ?
Solid are not be compressed easily because solid have fixed shape and fixed volume in between their particles their have no space   so they not compress easily but in gas between their particles their havehigh  space so they are compress easily

BABITA SHARMA [ROLL NO. 5]

                  LATENT HEAT OF VAPORISATION

1.Latent heat of vaporisation is the heat energy required to change 1KG of liquid to gas at atmospheric pressure at its boiling point.

                         LATENT HEAT OF FUSION

2.Latent heat of fusion is the amount of heat energy required to change 1kg of solid into liquid at its melting point 

DATE :- 12 APRIL,2016
 

VIBHAVARI VATS [ROLL NO. 16]

                  LATENT HEAT OF VAPORISATION  

LATENT HEAT OF VAPORISATION IS THE HEAT EVERGY REQUIRED TO CHANGE 1KG OF A

LIQUID TO GAS AT ATMOSPHERIC PRESSURE AT ITS BOILING POINT.

                              

                        LATENT HEAT OF FUSION 

LATENT HEAT OF FUSION IS THE AMOUNT OF HEAT ENERGY REQUIRED TO CHANGE 1KG

OF SOLID INTO LIQUID AT ITS MELTING POINT. 

   

DATE :- 12 APRIL,2016

  

Keshav Singh roll no 31

1.Latent heat of vaporisation is the heat energy required to change 1KG of liquid to gas at atmospheric pressure at its boiling point.
2.Latent heat of fusion is the amount of heat energy required to change 1kg of solid into liquid at its melting point

Date: 21/04/16

why does water come out from cucumber when we add salt to it ?

water come out from cucumber when we add salt to it because the content of salt that cucumber is less where as the salt in its  surrounding has high salt content , so to  get balance salt drawn from the  cucumber .

karan roll no 30

why solid are hard?
solid are hard because they have fixed shape and fixed volume and there particles are tightly packed so they have more force of attraction and there are no space between the particles.

when a solid melts,its temperature remains the same , so where does the heat go?
The heat is used to break the force of attraction and used in to convert it ice into water    

VIBHAVARI VATS[ ROLL NO.16]

   DIFFERENCE BETWEEN SOLIDS, LIQUIDS, & GASES   

DATE :-6 April ,2016

VIBHAVARI VATS [ROLL NO.16]

Question  :- Why Do Solids Have Fixed Shape ?

 

Answer :- The molecules in a solid are in fixed positions and are close together. Although the molecules can still vibrate, they cannot move from one part of the solid to another part.

 

 

Date:- 7 April, 2016

VIBHAVARI VATS [ROLL NO.16]

                         REASONS FOR THE QUESTIONS

Question :- Why The Table Is Hard ?

Answer:- The table is hard because in the table there are some particles and they are tightly packed.They cannot move, there force of attraction is very high, there are the

 reasons that's why table is very hard. 

Question:-Diver Is Able To Cut The Water?
Answer:- The particles of matter have space between them. Thus, one cannot cut through a solid easily but a diver is able to cut easily through water in a swimming pool.
  
Question:- How The Smell Of  Hot Sizzling Food Is Reached To Our Nose?
Answer:-Particles of matter are continuously moving. They posses the kinitic energy. As the temperature rises particles move faster. Thus the particles can carry smell of hot sizzling food in our nose.

 Date:-8 April, 2016

Ayush sharma roll no 25 ( matter in our surroundings)

Why the table is hard?
Answer:-The table is hard because in the table they have some particles and they are tightly packed .In this the inter molecular force of attraction is very high so they attract with each other.

Diver is able to cut the water?
Answer:-This shows that the particles of matter have space between them. This space is the maximum in the gases and the minimum in liquid. Thus, one cannot cut through a solid easily but a diver is able to cut easily through water in a swimming pool.

How the smell of hot sizzling food is reached to our nose?

Answer:-Particles of matter are continuously moving. They possess the kinetic energy. As the temperature rises, particles move faster. Thus, particles that carry smell of hot sizzling food move faster than the smell of the cold food. Therefore, the smell of hot sizzling food can reached to our nose. 

ANVEKSHA (ROLL NO :-3)

Chapter1 :- matter in our surroundins

*WHY DIVER IS ABLE TO CUT WATER?
ANS: The space is maximum in gasses and minimum in liquid, thus one cannot cut through a solid easily but a diver is able to cut water.
*WHY SMELL OF HOT SIZZLING FOOD REACHES IN OUR NOSE?
ANS: Particles of matter are continuously moving. They posses the kinitic energy. As the temperature rises particles move faster. Thus the particles can carry smell of hot sizzling food in our nose.

DATE :8-4-2016

Date: 07/04/2016                                                                                                                        
                             Chapter:1              
                                            Matter In Our Surrounding Properties of particles

Qns1. Why solids have its fixed size and shape?
Ans1.Solids have fixed shape because in solids the molecules are bonded tightly and there is very very less space in between molecules. So they have a definite shape and size.

Keshav Singh, Roll No. 31

ANS NO.1 The molecules are closely packed together and they attract each other.
ANS NO.2 The molecules are loosely packed and the inter molecular force of attraction is less.
ANS NO.3 The Gas react with Gas very fast.

Adeeb ahmad roll no. 22

Question - why do solid have fixed shape?

Answer - solid have fixed shape because the intermlicular space is low and force of attraction is very  high

Keshav Singh ,Roll No.31

 The molecules in a solid are in fixed positions and are close together. Although the molecules can still vibrate, they cannot move from one part of the solid to another part.

chapter 1     MATER IN OUR SURROUNDING   

DATE ; 6.4.2016   

THE PROPERTIES OF MATTER

1. THE PARTICLES OF MATTER ARE VERY SMALL.                                                                      
2. THE PARTICLES OF MATTER ARE CONTINESLY MOVING SO THEY HAVE KYNETIC ENERGY.                                                  
3. THE PARTICLES OF MATTER HAVE SPACE BETWEEN THEM.           

shobha( matter in surroundings)

Solids have fixed shape because its particles are tightly packed together.so this is the cause for solids rigidity

Anisha (roll no 1

Solids have fixed size becausethe  elements have fixed positions in space relative to each other. This accounts for the solid's rigidity

juhi (matter in our surroundings )

Solids have a fixed size and shape: 
- Because the atoms or molecules that compose the solid are packed closely together

Ramya roll no. 4 Matter in our surroundings

Solids have fixed shape because in solids the atoms are bonded tightly and there is very very less space in between atoms. So they have a definite shape and size.

vivek mehto roll 43

Some Characteristics of Gases, Liquids and Solids and the
gas	liquid	solid
assumes the shape and volume of its container	assumes the shape of the part of the container which it occupies	retains a fixed volume and shape
compressible	not easily compressible	not easily compressible
flows easily	flows easily	does not flow easily

karan roll no 30

Solids are hard  because they have molecules tightly packed to each other and do not exist in the liquid state.they have a perfect shape and volume and have Wight. they have more force of attraction

Amit Chauhan

 Three state of matter 

Some Characteristics of Gases, Liquids and Solids and the Microscopic Explanation for the Behavior
gas	liquid	solid
assumes the shape and volume of its container particles can move past one another	assumes the shape of the part of the container which it occupies particles can move/slide past one another	retains a fixed volume and shape rigid - particles locked into place
compressible lots of free space between particles	not easily compressible little free space between particles	not easily compressible little free space between particles
flows easily particles can move past one another	flows easily particles can move/slide past one another	does not flow easily rigid - particles cannot move/slide past one another

Amit Chauhan

Q1. What is matter ?
Ans Anything that occupies space possers mass
 and the presence of which can be felt anyone
 or more of our five senses is called matter

Adeeb ahmad siddiqui roll no 22

                                                  Matter in our surroundings
Question-Why do we observe that the level of water doesn't change even after  dissolving salt or sugar in it?

Answer- We observe that the level of water doesn't change even after dissolving salt or sugar in it because water and salt , both are made up of matter . Matter is made up of particles .These particles have spaces between them . So  , when we dissolve salt in water particles of salt get into the spaces between particles of water.
I will show you with the help of diagram.

salt dissolve in water

  

Vaishnavi Iyer Roll no:15

5th April 2016
Write the properties of particles:

• The particles of the matter are very small.
• The particles of matter are continuously moving means that they have kinetic energy .
• The particles of matter have space between them.

6th April 2016

Question:

Why the solids have definite shape?

Answer:

The shapes in between the constituent particles and kinetic energy of the particles are minimum  and arrangements  of particles is most ordered in case of solids. Thus the solids have definite shape.

7 April 2016

GIVE REASONS

1) Why the table is hard?

     The solids like table are hard because the space between the constituent particles are minimum and are tightly packed with each other , and the intermolecular force of attraction is high in case of solids .

2)  Why the diver is able to cut water ?

       The intermolecular force of attraction is less in case of water and it has compressibility. Thus the diver able to cut the water.

3) Why the smell of hot sizzling food reaches our nose?

      When the food is cooked the particles of the food are release and accumulate into the air by the process called diffusion. When the air traveles with the gases it enters into our nose. By this way we can able to smell the sizzling food.

12 April 2016

1) What is latent heat of fusion ?
     The amount heat energy  that is required  to change      1kg of solid intI liquid  at atmospheric pressure at its melting point is known as the latent heat of fusion .
2) What is latent heat of vaporisation ?
    Particles in the steam, that is water vapour at 373K (100°c)  have more energy than water at the same temperature.This is because particles in steam have absorbed  extra energy in the form of heat of vaporisation.

 13 April 2016
1) Name the factors affecting evaporation

•  Temperature - the rate of evaporation is directly proportional to the rise in temperature. If the surface area is increased , the rate of evaporation increases
•  Surface area - if the surface area is increased, the rate of evaporation increases
• Humidity -  humidity is the amount of water vapour present in air. If the amount of water in air is already high , the rate of evaporation decreases.
• Wind speed -  with the increase in wind speed, the particles of water vapour move away with the wind vapour in the surrounding.    

  Chapter2 THE        FUNDAMENTAL      UNIT OF LIFE

            

  21 April 2016

 

1) Why does the water come out from the cucumber when we add salt in it?

    Osmosis is the passage of water from the high water concentration  to low water concentration .In the case of  cucumber the cell of the cucumber contains more water than salt . Thus to maintain the concentration the water come out from the cucumber when the salt is added. 

 

   24 April 2016

1) What is diffusion and osmosis?

       Diffusion :   It is the process of movement  of particles from their higher concentration to their lower concentration .

For example : exange of gases by stomata.

  Osmosis: It is the process of movement of molecules from their higher concentration to their lower concentration in presence of semi permeable membrane.

For example: The movement of water from in and out of the cell takes place by the process of osmosis.

Soubhagya Singh Roll No-46 This is my Home work Page and I will do my home work regularly

CHAPTER 1 -MATTER  IN  OUR  SURROUNDINGS

QUESTION 1-What  is  matter?

ANSWER1-We look  at our surrounding, we see a large variety of things with different shapes, size and textures.Everything in the  universe is made up of material which scientists have named matter'. The air we breathe,the food we eat, stones,clouds, stars, plants and animals, even a small drop of water or a particle of sand- every thing is called matter.

QUESTION 2- Why do we observe that the level of water doesn't change even after dissolving salt and sugar in it?

ANSWER 2-  The  particles of sugar, salt got evenly distributed in  water.Similarly when we make tea,           coffee or lemonade, particles of one type of matter get into the spaces between the particles of others. These shows that there is enough space between particles of matters.

QUESTION 3-Write property of particles?

ANSWER 3- 1.Particles of matters have space between them.

                      2.The particles of matter are very small, they are small beyond our imagination.

                      3.They   are continously moving.

                      4.Paricles of matter are very small.

QUESTION 4- Why the solid have fixed shape?

ANSWER    4- Solid is a matter and every matter  have a definite shape and volume. So the  molecules in a solid are  in a fixed place and are in close to each other.The molecules can vibrate but cannot move from one part of the solid to a another part.

QUESTION 5-Give  Reasons:-

                       (i) Table is hard

                      (ii) Diver is able to cut the water

                      (iii)The smell of hot sizzling food reach to our nose

ANSWER 5:-

                      (i) Table is hard because the molecules are and they have no space to move.

                     (ii)Particles of water atract each other but attraction  is not strong enough to prevent the diver 

                          to cut through water.

                     (iii)The smell of hot sizzling food  reaches us because particles of food diffuse faster in air when 

                          hot whereas when food is cold it diffuse slower so it take more time than hot sizzling food.

SOUBHAGYA SINGH Roll no-46

Properties of particles

1) The particles of the matter are very small

2) The particles of matter are

VIBHAVARI VATS [ROLL NO. 16 ] {Properties of Matter}

     PROPERTIES OF PARTICLES OF MATTER 

                                    PROPERTIES OF PARTICLES OF MATTER ARE :-

•  Particles Of  Matter Have Space Between Them.
• Particles Of  Matter Are Continuously Moving.
• Particles Of  Matter Attract Each Other.
• The Particles Of  Matter Are Very Small They Are Small Beyond Our Imagination.

           Dated : 5 April, 2016

juhi ( properties of particles )

1 particles are very small
2 these are continously moving
3 these have spaces betwwen them

anisha ( Matter in our surroundings )

Properties of particles are : One important property is that these particles move continuosly . Second property is that these particles have space between them .

shobha roll no 14

Properties are : These are very small . These have space between them . These particles have kinetic energy

Ramya (roll no. 04 )Matter in our surroundings

Properties of particles in matter : 1.these are very small in size 2.these particles have kinetic energy ,which means that they are continously moving . 3.these particles have space between them

SAKSHI Roll No. 12

 THIS IS MY HOMEWORK PAGE

  AND I WILL DO MY HOME WORK REGULARLY

Keshav Singh ,Roll No.31

Properties of particles are:
[a] The particles of matter are very small.
[b] The particles of matter are continuosly moving means the have kinetic energy.
[c] The particles of matter have space between .

LIPIKA [roll no. ]

Amit Chauhan roll no 24

This is my home work page . I will do my home work regularly

karan bisht rollno 30

ANS= as water is a matter and it is made up of particles and particle of matter have space between them so, when we pour salt in it water particles of salt will settle in the gap between the particles of the water. as thermal energy got converted into kinetic energy in water so, particles moves in the water as a substance want to become stable so,it decrease its surface area and after some time it become invisible       

LIPIKA TANWER

THIS IS MINE HOME  WORK PAGE ..

I WILL DO MY HOME WORK DAILY

Dipanshu roll no. 26

i will do my homework regularly

Abhishek singh (roll.no=25)

   IS MATTER AROUND US PURE

Exercise

Q1- 1. Which separation techniques will you apply for the separation of the following?

(a) Sodium chloride from its solution in water.
 Evaporation

(b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
 Sublimation

(c) Small pieces of metal in the engine oil of a car.
 Filtration or Centrifugation or decantation

(d) Different pigments from an extract of flower petals.
 Chromatography

(e) Butter from curd.
 Centrifugation

(f) Oil from water.
 Using separating funnel

(g) Tea leaves from tea.
 Filtration

(h) Iron pins from sand.
 Magnetic separation

(i) Wheat grains from husk.
 Winnowing

(j) Fine mud particles suspended in water.
 Centrifugation

Q2- Write the steps you would use for making tea. Use the words: solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Answer

First, water is taken as a solvent in a saucer pan. This water (solvent) is allowed to boil. During heating, milk and tea leaves are added to the solvent as solutes. They form a solution. Then, the solution is poured through a strainer. The insoluble part of the solution remains on the strainer asresidue. Sugar added to the filtrate, which dissolves in the filtrate. The resulting solution is the required tea.

Q3- . Pragya tested the solubility of three different substances at different temperatures and collected the data as given below( results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).

(a)  What mass of potassium nitrate would be needed to produce a saturated solution of potassium nitrate in 50 grams of water at 313 K?

(b)  Pragya makes a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would she observe as the solution cools? Explain.

(c)  Find the solubility of each salt at 293 K. What salt has the highest solubility at this temperature?

(d)  What is the effect of change of temperature on the solubility of a salt? 

Answer

(a) Since 62 g of potassium nitrate is dissolved in 100g of water to prepare a saturated solution at 313 K, 31 g of potassium nitrate should be dissolved in 50 g of water to prepare a saturated solution at 313 K.

(b) The amount of potassium chloride that should be dissolved in water to make a saturated solution increases with temperature. Thus, as the solution cools some of the potassium chloride will precipitate out of the solution.

(c) The solubility of the salts at 293 K are:
Potassium nitrate – 32 g
Sodium chloride – 36 g
Potassium chloride – 35 g
Ammonium chloride – 37 g

Ammonium chloride has the highest solubility at 293 K.

(d) The solubility of a salt increases with temperature.

Q4- . Explain the following giving examples:

(a) Saturated solution
(b) Pure substance
(c) Colloid
(d) Suspension

Answer

(a) Solution in which no more solute can be dissolved at a particular temperature is known as saturated solution. For example in aqueous solution of sugar no more sugar can be dissolved at room temperature.

(b) A pure substance is a substance consisting of a single type of particles i.e., all constituent particles of the substance have the same chemical properties. For example water, sugar, salt etc.

(c) A colloid is a heterogeneous mixture whose particles are not as small as solution but they are so small that cannot be seen by naked eye. When a beam of light is passed through a colloid then the path of the light becomes visible. For example milk, smoke etc.

(d) A suspension is a heterogeneous mixture in which solids are dispersed in liquids. The solute particles in suspension do not dissolve but remain suspended throughout the medium. For example Paints, Muddy water chalk water mixtures etc.

Q5- . Classify each of the following as a homogeneous or heterogeneous mixture.
Soda water, wood, air, soil, vinegar, filtered tea

Answer

Homogeneous mixtures: Soda water, air, vinegar, filtered tea
Heterogeneous mixtures: Wood, soil
Note: Pure air is homogeneous mixture but Polluted air is heterogeneous mixture.

Q6- . How would you confirm that a colourless liquid given to you is pure water?

Answer

Take a sample of colourless liquid and put on stove if it starts boiling exactly at 100 ºC then it is pure water. Any other colourless liquid such as vinegar always have different boiling point. Also observe carefully that after some time whole liquid will convert into vapour without leaving any residue.

Q7- . Which of the following materials fall in the category of a "pure substance"?

(a) Ice
(b) Milk
(c) Iron
(d) Hydrochloric Acid
(e) Calcium oxide
(f) Mercury
(g) Brick
(h) Wood
(i) Air

Answer

The following materials fall in the category of a "pure substance":
(a) Ice
(c) Iron
(d) Hydrochloric acid
(e) Calcium oxide
(f) Mercury

Q8- . Identify the solutions among the following mixtures:

(a) Soil
(b) Sea water
(c) Air
(d) Coal
(e) Soda water

Answer

The following mixtures are solutions:
(b) Sea water
(c) Air
(e) Soda water

Q9- . Which of the following will show the "Tyndall effect"?

(a) Salt solution
(b) Milk
(c) Copper sulphate solution
(d) Starch solution

Answer

Tyndall effect is shown by colloidal solution. Here milk and starch solution are colloids therefore milk and starch solution will show Tyndall effect.

Q10-. Classify the following into elements, compounds and mixtures:

(a) Sodium
(b) Soil
(c) Sugar solution
(d) Silver
(e) Calcium carbonate
(f) Tin
(g) Silicon
(h) Coal
(i) Air
(j) Soap
(k) Methane
(l) Carbon dioxide
(m) Blood

Answer

Elements: Sodium, Silver, Tin and Silicon.

Compounds: Calcium carbonate, Methane and carbon dioxide.

Mixtures: Soil, Sugar, Coal, Air, Soap and Blood.

Q11- . Which of the following are chemical changes?

(a) Growth of a plant
(b) Rusting of iron
(c) Mixing of iron fillings and sand
(d) Cooking of food
(e) Digestion of food
(f) Freezing of water
(g) Burning of candle

Answer

The following changes are chemical changes:
(a) Growth of a plant
(b) Rusting of iron
(d) Cooking of food
(e) Digestion of food

(g) Burning of candle