We observe that land becomes barren soon after monsoon. But in the next monsoon it flourishes again with varieties we observed in season earlier. How you think it takes place?

Apparatus: Copper wire, iron nail, beaker or big test tube, etc. Chemicals: Aqueous solutions of ferrous sulphate and copper sulphate. Procedure: i. Take a clean copper wire and a clean iron nail. ii. Dip the copper wire in ferrous sulphate solution and the iron nail in copper sulphate solution. iii . Keep on observing continually at a fixed interval of time. How did you recognize that a reaction has taken place?

Observe the following diagram and write the answers of the following question After completion of a period, what change does take place in the electronic configuration of the next element?

Answer the following questions: Observe the following diagram and write the answer the following questions: After completion of a period , what change does take place in the electronic configuration of the next element?

Veena observes that during winter setting of milk into curd takes more time while during summer, the same process happens faster. She asks about this difference in time taken to her elder sister. She also asks her sister about why certain reactions occur rapidly while others occur slowly. Her sister explains her about the various factors that affect the rate of chemical reactions. Based on the above scenario, answer the following questions. Why do you think setting of curd occur at different rates during different seasons?

Observe the garbage collected in the dustbin of you classroom and make a list of the various material in it. Discuss with your teacher, how these materials can be properly disposed off. Can we do the same with the garbage generated in our house? Think about it.

Solve the following problems. We observed the traffic lights at three different squares on the same big road. They turn green every 60 seconds, 120 seconds and 24 seconds. When the signals are switched on at 8 o’clock in the morning, all lights were green. How long after that will all three signals turn green simultaneously again?

Do you have experience of the instances given below? : A plastic comb or ruler rubbed on dry hair attracts pieces of paper. : If we pass near a polyester curtain again and again, it gets attracted towards us. : If we rub a blanket with our hands and take it near a metal object, a spark is seen in the dark. : What do the above observations tell us?

Let’s try this : Fix a bar magnet to a stand as shown in the figure. Let it become steady. Take another bar magnet near the hanging bar magnet. Observe what happens. Do the same again and again, exchanging the ends of a magnet. What do you see ?