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Class XI Chemistry: Study guide & notes by Vineeta Agrawal and Rajesh Sharma DPS Mathura Refinery Nagar Mathura - 281006 (UP Unit-1.doc : SOME BASIC CONCEPTS OF CHEMISTRY View           Download Unit-2.doc : STRUCTURE OF ATOM By: Vineeta Agrawal View           Download Unit-3.doc : CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES View            Download Unit-04.doc CHEMICAL BONDING AND MOLECULAR STRUCTURE View           Download UNIT 5.doc : STATES OF MATTER View          Download Unit-06.doc THERMODYNAMICS View         Download Unit-07.doc EQUILIBRIUM View           Download Unit-08.doc REDOX REACTIONS View            Download UNIT-09.doc : HYDROGEN View           Download Unit-10.doc THE s -BLOCK ELEMENTS View Download For more study material click Class11 chemistry

1. The curd contains -----bacteria which helps to change the milk into curd Lacto bacillus 2. -------------is used for commercial production of alcohol and wine. Yeast 3. Process of conservation of sugar into alcohol is known as ---------------- Fermentation. 4. Disease causing microorganisms are called ------------------------- Pathogens 5. Virus is a Latin word which means ----------------- Poison 6. Virus is a Latin word which means------------------. Poison 7. ------------ are on the border line between living and non-living organisms Virus

1.Fill in the blanks : (1) Microorganisms can be seen with the help of a .......................... . (2) Blue green algae fix .......................... directly from air to enhance fertility of soil. (3) Alcohol is produced with the help of .......................... . (4) Cholera is caused by a .......................... . (5) Coci bacteria are ...................... in shape Ans. (1) microscope. (2) nitrogen (3)yeast. (4) bacteria. (5) round. Q.What are microorganisms ? Ans. The living organisms aound us which we normally cannot see. These are called microorganisms or microbes. Q.Into how many groups are microorganisms classified ? Ans. Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae. But viruses are also microscopic. Q. Viruses are considered as being on the border line between living and non-living organisms,Why? Ans: Viruses is nonliving out side living cells but grows and multipli

The yeast multiply by a process called (a)     Binary fission (b)    Budding (c)     Spore formation (d)    None of the above The example of protozoan is (a)     Penicillium (b)    Blue green algae (c)     Amoeba (d)    Bacillus The most common carrier of communicable diseases is (a)     Ant (b)    Housefly (c)     Dragonfly (d)    Spider The following is an antibiotics (a)     Alcohol (b)    Yeast (c)     Sodium bicarbonate (d)    Streptomycin Yeast produces alcohol and carbon dioxide by a process called (a)     Evaporation (b)    Respiration (c)     Fermentation (d)    Digestion The algae commonly used as fertilizers are called (a)     Staphylococcus (b)    Diatoms (c)     Blue green algae (d)    None of the above

1. A machine gun can fire bullet of 50gm at speed of 2000m/s ,the man holding the gun can exert an average force of 200N against the gun .  Calculate  the maximum number of bullet which he can fire per minute  ( Ans: 120 ) 2. A  machine gun can fire 20 bullet per second ,if the speed of the bullet is 100m/s and if each bullet is of weight 100gms , then calculate force  require  to hold the gun in its position.  ( Ans: 200N ) 3. A man in a circus show jumps from a height of 10m and is caught by a net spread below him. The net sags below by 2m . Find the force exerted by the net on the man to stop him. Mass is 60kg and acceleration is 10m/s 2 .  (Ans: 300N) 4. A machine gun is fitted on a trolley of mass 2000kg on a horizontal frictionless surface. If the gun fires bullet each of mass  10gm with a velocity of 500m/s with respect to the trolly and if  the number  of bullet fired per second  is 10 then calculate the average thrust exerted by ejected bullet  on the system   (Ans: 50N) 5.

CBSE PHYSICS: Enrich your study: IX:Force and laws of motion sol... : CBSE PHYSICS: IX:Force and laws of motion solved Problems 1. An athlete runs a certain rest before taking a long jump. Why? Solution: An... CBSE PHYSICS: IX:Force and laws of motion solved Problems  1. An athlete runs a certain rest before taking a long jump. Why? Solution: An athlete runs a certain distance to accelerate himself and gain enough momentum so that he can jump through the maximum possible length. 2. Springs are provided in car seats. Why? Solution: The springs in the car seats absorb shock (sudden jumps) due to the roughness of the road. Thus, making the ride more comfortable. 3. A gun of mass 1500 kg fires a shell of mass 15kg with velocity 150 m/s. calculate velocity of recoil of the gun. Solution: Before firing, total momentum of the gun and shell is = 0 (they were all at rest) After firing, the momentum of the shell = 15 X 150 = 2250 Ns The momentum of the gun is = 1500v Ns By conservat

chemistry X : 10th Acid Base and Salt:Solved Edugain questions Q. 1.  What happens if sodium hydroxide is added to cupper    ammonium sulphate solution and what is the inference? Answer:  When sodium hydroxide is added to cupper  ammonium sulphate solution, no blue precipitate of Cu(OH) 2  is seen, which is normally  observed  for Cu 2+  ion. Hence it is an example of a complex salt. Q 2. When lead dioxide reacts with concentrated HCl and produces a salt and water, the reaction is  not called  a neutral reaction why? Answer:  For a reaction to be called a neutral reaction the products should be only salt and water. But in the above reaction, Cl 2  gas is also  liberated . Q 3.Define a base and acid in terms of proton. Answer:  A base is a proton acceptor and an acid is a proton donor. Q 4. Answer these:   1) Name the anions that can be detected in the laboratory using dilute HCl or dilute H 2 SO 4  and give the ionic equation common to both reactions.   2) Which property of the a