Knowledge hub

Ques 1 : Why should a magnesium ribbon be cleaned before burning in air? Ans 1: Magnesium is very reactive metal like (Na, C a, etc.). When it expose to air it reacts with oxygen to form a layer magnesium oxide (Mg O) on its surface.                  Mg +  O 2 → 2 Mg O This layer of magnesium oxide is quite stable and prevents further reaction of magnesium with oxygen. The magnesium ribbon is cleaned by sand paper to remove this layer so that the underlying metal can be used for the reaction. «« Chapter 1 NCERT Solution                                            Next question »»

Ques : Di nitrogen and dihydrogen react with each other to produce ammonia according to the following chemical equation:                        N 2 ​ +  H 2  ​ (g)→2  NH 3  ​   (i) Calculate the mass of ammonia produced if 2.00×10 2 g di nitrogen react with 1.00×10 3 g of dihydrogen.  (ii) Will any of the two reactants remain un reacted? (iii) If yes, which one and what would be its mass? Ans : (i) 28.0 g of  N 2  require 6.0 g of  H 2  to produce =34.0 g of NH  ​    2.00 × 10³ g of N 2  will produce = 28/34 ×2.00×10³g of  NH 3    =2.43×10³ g of  NH 3                  = 2430 g  NH 3 ​   (ii) Yes, dihydrogen will remain un reacted to some extent.  (iii) Amount of hydrogen that remains un reacted. 28.0 g of N 2  require 6.0 g of  H 2 ​   2.00 g×1...

Ques 1 : What do you mean by sports journalism? Ans : In sports journalism we mean that we can gather information regarding all sports activities and to collect all different types of material required for physical education. Such physical education teachers who have skill in communicating by oral or writing can avail their career option in the field of sports journalism.  Ques 2 : What do you mean by Health related careers? Ans : In the modern world, people are more aware of their health and health related issues. Each and every person is curious about their health. He remain to be hale and healthy. He wants to adopt a healthy life style. So there is an increment in job opportunities in health related careers in field of physical education. The no. of health and weight control clubs has increased tremendously. The another career related to health career is athletics training.  Ques 3 : What is the objective of physical education? Ans : The main obje...

Forgot Password? Sign In https://www.instagram.com/dyi/download/auth/cF9hbGFrXzAy/?dyi_job_id=742390740259005

Ques 1: “Physical Eduction is the sum of changes in an individual caused by experience centring motor activity” Who said this? (a) Prince martin  (b) Millions (c) Charls A.Butchar  (d) Cassidy Ans :  (d) Cassidy Ques 2: “Physical Education is the sum of men’s physical activities selected as to kind and conducted as to outcomes” who said this? (a) C.C.Covel  (b) Charls A Butcha (c) Williams  (d) J.B. Nash Ans :  (c) Williams Ques 3 : How many objectives of physical Education are there? (a) Four  (b) Five (c) Three  (d) Six Ans : (b) Five Ques 4 : What is the aim of physical Education? (a) Physical development  (b) Motor development (c) Mental Development  (d) All Round development Ans : (d) All Round development Ques 5: Sports management is based upon....? (a) Efficient and Talented officials  (b) Smart and clever officials (c) Weak and Greedy officials  (d) None of these  Ans : (a) Efficient and Talented of...