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Introduction Carbon is an element which is of immense significance to us in both its elemental form and in the combined form. Bonding in Carbon - The Covalent Bond Although there are more than hundred elements around us we do not find these elements in their native form in nature. This is because most of these elements are highly reactive. Properties of Covalent Compounds A covalent bond can be formed in different ways. When a bond is formed by mutual sharing of one pair of electrons it is known as a 'single covalent bond', or simply 'a single bond'. Types of Covalent Bonds Types of covalent bonds are Single Bond, Double Bond , Triple Bond. Tetravalency in Carbon A carbon atom has a total of six electrons occupying the first two shells, i.e., the K-shell has two electrons and the L-shell has four electrons. Allotropes of Carbon The existence of one element in different forms, having different physical properties, but similar chemical properties is known as allotropy. Am...

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Class VII, NCERT (CBSE) Mathematics Text Book Exercise 11.1 Solution (Page 208 - 209) Q1: The length and the breadth of a rectangular piece of land are 500 m and 300 m respectively. Find (i) Its area (ii) The cost of the land, if 1 m2 of the land costs Rs 10,000. Ans: (i) Area = (length × breadth) = 500 × 300 = 150000 m2 (ii)Cost of 1 m2 land = Rs 10000 Cost of 150000 m2 land = 10000 × 150000 =

POLITICAL SCIENCE CLASS X CBSE DEMOCRACY AND DIVERSITY STORY OF MEXICO OLYMPICS In 1968, Olympics held at Mexico City, in the medal ceremony of 200m race, where gold and bronze medals were won by the AFRICAN –AMERICANS & the silver was bagged by the white. In the ceremony Tommie Smith & John Carlos (African- Americans) stood on the dice with clenched fists upraised & heads bowed while the American anthem was played. They received their medals wearing black socks & no shoes to represent ‘BLACK POVERTY.’ The silver medalist, white Australian athlete, Peter Norman, wore human rights badge on his shirt to show his support to the two Americans. Q. Why did Tommie & Smith wear black socks & no shoes? --To represent Black poverty. Q. What did their clenched fists &black gloves represent? --They meant to symbolize the Black Power. Q. What did the two players intend to do with this kind of gesture? They wanted to draw the international attention to racial discriminati...

POLITICAL SCIENCE CLASS X CBSE POLITICAL PARTIES CHALLENGES TO POLITICAL PARTIES We know that how crucial political parties are for the democracy. They are the most visible face of the democracy and people blame them for whatever is wrong in the working of democracy. This is a case of our country too. Popular dissatisfaction and criticism has focused on four problem areas in the working of political parties. 1. LACK OF INTERNAL DEMOCRACY (with in the party): all over the world there is a tendency in the political parties towards the concentration of power in one or few leaders at the top. --parties do not keep membership registers, do not hold organizational meetings and conduct internal elections regularly. --ordinary members do not get sufficient information on what happens inside the party. --leaders assume greater power to make decisions in the name of party. --more than loyalty to the party principles and policies, personal loyalty to the lead...

POLITICAL SCIENCE CLASS X CBSE POPULAR STRUGGLES AND MOVEMENTS POPULAR STRUGGLES IN NEPAL AND BOLIVIA MOVEMENT FOR DEMOCRACY IN NEPAL - -SECOND MOVEMENT FOR DEMOCRACY. Nepal witnessed an extraordinary popular movement in April 2006.The movement aimed at restoring democracy; it was aimed at regaining popular control over govt. from the king. History: Nepal a third wave country, had won democracy in 1990. --King was formally the head of the state but the real power was excerised by the elected representatives. --The king Birendra, was the one who accepted this transition from absolute monarchy to constitutional monarchy, he and his family was massacred in 2001. --King Gyanendra the new king of Nepal was not prepared to accept democratic rule, on February 2005 he dismissed the Prime minister and dissolved the popularly elected Parliament. Events during the popular revolt: 1.All the political parties in the parliament formed an alliance--Seven party alliances--SPA and called for four day s...

Question (1):   What does the word 'petite' mean? 1. strong 2. small 3. neat 4. clean Ans:   2 Question (2):   What was almost a routine affair for Babuli during his student days? 1. working in the city 2. writing to his elder brother 3. going home in the rickety bus 4. reading big books Ans:   3 Question (3):   What was written in the elder brother's letter? 1. That they were missing him in the village 2. That there was to be a partition 3. That there was a festival 4. That he would get money Ans:   2 Question (4):   How many days were left for the partition? 1. A week 2. A month 3. A day 4. Three days Ans:   1 Question (5):   How much money was expected for Babuli's land? 1. Seven thousand 2. Twenty thousand 3. Ten thousand 4. Forty thousand Ans:   2 Question (6):   What makes Babuli think of the butcher? 1. Hunger 2. Wife's heartlessness 3. The i...

Question (1):   Describe Babuli's feelings when he hears his wife discussing the things they would buy with the money they would get after selling their share of the land. Answer:   Babuli thinks of the butcher. He feels his wife is insensitive and heartless. But finally, he also goes with her to the shops to estimate the costs of various commodities. Question (2):   What were the changes Babuli noticed in the village home when he reached there? Answer:   When Babuli reached his village home no one came to receive him. There was the silence of a graveyard. His sister-in law and nephews did not rush out to greet him. His second brother and his wife were nowhere to be seen. Question (3):   How much did the second brother offer Babuli to buy his share of land? Answer:   Babuli was offered Rs. 18,000/- to buy his share of land. Question (4):   Quote two instances from the story highlighting his elder brother's sacrificing nature. ...

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