NCERT solutions for Science

      NCERT solution  > Science > Class 10th    NCERT solution for class 10 //Science // Chapter 14  -- Sources of energy                      Page number 243  Q1. What is a good source of energy ? Answer   There are so many good sources of energy and their shows the following characteristics  It should be easily accessible It should be large amount of work per unit volume  It should be easy to store ,transport and production  It should be economically cheap source Q2. What is a good fuel  ? Answer -  A good fuel is burn completely without producing smoke or Ash and it produces a large amount of heat by burning a small quantity of it .It shows the all characteristics of good sources of energy Q3. If you could use any source of energy for heating your food which one would you use and why  Answer.  - W e would use oven or heater i...

 NCERT solution   > Class 10 > Science NCERT solution for class 10 //  Science  // Chapter 5  - Periodic classification of element s   Chapter 5  - Periodic classification of element s                      Page number 81  Q1. Did Dobereiner's triads also exist in the columns of newlands octaves compare and find out  ?  Answer  -  Dobereiner's triads also exist in the column of newland octaves   Ex-  Lithium ( Li) , Sodium (Na) and Potassium(K) institute of trades if we consider Li as a first element then the eight element from it is Na and if we consider Na as the first element then the eight element from it is K Q2. What were the limitations of Dobereiner's classification  Answer  -   Dobereiner's only form 3 traits from the elements known at that time  The classification of known elements could not be possible ...

               NCERT solution  > Science > Class 10th > Chapter 4 -Carbon and its compound    N CERT solution for class 10th // Science / / Chapter 4  -Carbon and its compound                          Page number 61   Q1. What would be the electron dot structure of carbon dioxide which has the formula    CO 2  Answer  .  Electron dot structure of    CO 2  is          Q2. What would be the electron dot structure of molecules of sulphur which is made up of eight atoms of sulphur ( Hint- the 8 atoms of sulphur are joined together in the form of a ring)  Answer                            Page number 68  Q 3. How many structural isomers can you draw for pentane  Answer  P...

  NCERT solution  > Class 9th  > Science >Chapter 5 The fundamental unit of life  NCERT solution for class 9th //Science  //  Chapter 5 -   The fundamental unit of life                       Page number 59  Q 1. Who discovered cells and how ?  Answer  .-  Robert hook was discovered cell in 1665 he observed the cell in a thin slice of cork .He appeared like a small compartment when he viewed through the microscope Q2. Why is the cell called the structural and functional unit of life  Answer    A cell have a capability in carrying out all the fly functions like nutrition and respiration x-ray excretion circulation etc hence it is called functional unit of life. The cell is the smallest unit of life and all living beings are made up of cells so it is a structural unit of life                 ...