Which of these is not a valid reason for arguing that there is a lesser possibility
[question] Question. Which of these is not a valid reason for arguing that there is a lesser possibility of famine in a democratic country? (a) Opposition parties can draw attention to hunger and starvation. (b) Free press can report suffering from famine in different parts of the country. (c) Government fears its defeat in the next elections. (d) People are free to believe in and practise any religion. [/question] [solution] Solution: Option ‘d’ is not a valid reason for arguing that there is a...
Read More →Why are carbon and its compounds used
[question] Question. Why are carbon and its compounds used as fuels for most applications? [/question] [solution] solution: When carbon is heated in presence of excess of air or oxygen, it forms carbon dioxide. During its formation, a large amount of heat and light are released. Further, once ignited, carbon and its compoundskeep on burning without needing additional heat energy. [/solution]...
Read More →Each of these statements contains a democratic and an undemocratic element.
[question] Question. Each of these statements contains a democratic and an undemocratic element. Write out the two separately for each statement. (a) A minister said that some laws have to be passed by the parliament in order to conform to the regulations decided by the World Trade Organisation. (b) The Election Commission ordered re-polling in a constituency where large scale rigging was reported. (c) Women’s representation in the parliament has never reached 10 per cent. This led women’s organ...
Read More →Which of these is not a good argument in favour of democracy?
[question] Question. Which of these is not a good argument in favour of democracy? Why? (a) People feel free and equal in a democracy (b) Democracies resolve conflict in a better way than others (c) Democratic government is more accountable to the people (d) Democracies are more prosperous than others [/question] [solution] Solution: The argument ‘d’, which states that “Democracies are more prosperous than others”, is not a good argument in favour of democracy. This is because some democracies l...
Read More →Find the zeros of the following quadratic polynomials and verify
[question] Question. Find the zeros of the following quadratic polynomials and verify the relationship between the zeros and the coefficients. (i) $x^{2}-2 x-8$ (ii) $4 \mathrm{~s}^{2}-4 \mathrm{~s}+1$ (iii) $6 x^{2}-3-7 x$ (iv) $4 u^{2}+8 u$ (v) $t^{2}-15$ (vi) $3 x^{2}-x-4$ [/question] [solution] Solution: (i) $x^{2}-2 x-8=x^{2}-4 x+2 x-8$ $=x(x-4)+2(x-4)=(x+2)(x-4)$ Zeroes are – 2 and 4. Sum of the zeros $=(-2)+(4)=2=\frac{-(-2)}{1}=\frac{-(\text { Coefficient of } \mathbf{x})}{\left(\text { ...
Read More →Why does micelle formation take place when soap is added to water?
[question] Question. Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents like ethanol also? [solution] solution: A molecule of soap has two dissimilar ends. At one end is the hydrocarbon chain which is water repellent. At the other end carboxylate anion is present which is water soluble end. When soap is dissolved in water, many molecules come together and form a group called micelle, these micelles are formed because their hydrocarbon ch...
Read More →Here is some information about four countries.
[question] Question. Here is some information about four countries. Based on this information, how would you classify each of these countries. Write ‘democratic’, ‘undemocratic’ or ‘not sure’ against each of these. (a)Country P: The parliament cannot pass a law about the army without the consent of the Chief of Army (b) Country Q: The parliament cannot pass a law reducing the powers of the judiciary (c) Country R: The country’s leaders cannot sign any treaty with another country without taking p...
Read More →Compare all the proposed models
[question] Question. Compare all the proposed models of an atom given in this chapter. Thomson’s model Rutherford’s model Bohr’s model [/question] [solution] Solution: An atom consists of a positively charged sphere with electrons embedded in it. An atom consists of a positively charged particles concentrated at the centre known as the nucleus. The size of the nucleus is very small as compared to the size of the atom. The electrons revolve around the nucleus in well-defined orbits. There are onl...
Read More →Here is some information about four countries
[question] Question. Here is some information about four countries. Based on this information, how would you classify each of these countries. Write ‘democratic’, ‘undemocratic’ or ‘not sure’ against each of these. (a) Country A: People who do not accept the country’s official religion do not have a right to vote (b) Country B: The same party has been winning elections for the last twenty years. (c) Country C: Ruling party has lost in the last three elections (d) Country D: There is no independe...
Read More →How can ethanol and ethanoic acid be differentiated
[question] Question. How can ethanol and ethanoic acid be differentiated on the basis of their physical and chemical properties? [/question] [solution] solution: [/solution]...
Read More →Which of the following positions can contribute to democracy at the global level?
[question] Question. Which of the following positions can contribute to democracy at the global level? Give reasons for your answer in each case. (a) My country gives more money to international institutions. Therefore, I want to be treated with more respect and exercise more power. (b) My country may be small or poor. But my voice must be heard with equal respect because these decisions will affect my country. (c) Wealthy nations will have a greater say in international affairs. They cannot let...
Read More →Describe Bohr’s model of the atom.
[question] Question. Describe Bohr’s model of the atom. [/question] [solution] Solution: Bohr’s model of the atom Neils Bohr proposed the following postulates regarding the model of the atom. (i) Only certain orbits known as discrete orbits of electrons are allowed inside the atom. (ii) While revolving in these discrete orbits, the electrons do not radiate energy. These discrete orbits or shells are shown in the following diagram. The first orbit (i.e., for n = 1) is represented by letter K. Sim...
Read More →What is an homologous series?
[question] Question. What is an homologous series? Explain with an example [/question] [solution] solution: A family of organic compounds having the same functional group, similar chemical properties and the successive members of which differ by a $\mathrm{CH}_{2}$ group or 14 mass units. e.g. $\mathrm{CH}_{3} \mathrm{OH}$ (methanol) $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}$ (ethanol) $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$ (propanol) They constitute homologous series o...
Read More →Which freedoms are usually taken away when a democracy is overthrown by the military?
[question] Question. Which freedoms are usually taken away when a democracy is overthrown by the military? [solution] Solution: When democracy is overthrown by the military, freedom is curbed and the following incidents are usually witnessed: 1. The military does whatever it wishes to do and no one has the authority to question them. 2. The military government tortures harass, imprisons, and also kills people who had gone against them during their takeover. Moreover, citizens are not allowed to ...
Read More →What are the limitations
[question] Question. What are the limitations of Rutherford’s model of the atom? [/question] [solution] Solution: A model of the atom was described by the British physicist Ernest Rutherford in 1911, and is known as the Solar System model. It is very simple, and is still used to teach elementary atomic structure to school children. • An atom consists of a central nucleus. This nucleus is composed of positively charged protons, and electrically uncharged (neutral) neutrons. • Negatively charged e...
Read More →What are the difficulties people face in a non-democratic country
[question] Question. What are the difficulties people face in a non-democratic country? Give answers drawing from the examples given in this chapter. [/question] [solution] Solution: Citizens of non-democratic countries face a lot of difficulties. These are listed below: 1. They are not allowed to choose their leader or raise a voice against changing their leader. 2. They aren’t entitled to form political parties without the consent of the one in power. They do not have the rights to form indepe...
Read More →Draw the electron dot structure of
[question] Question. Draw the electron dot structure of (a) Ethanoic acid (b) $\mathrm{H}_{2} \mathrm{~S}$ (Hydrogen sulphide) (c) Propanone (d) $\mathrm{F}_{2}$ (Fluorine) [solution] solution: (a) Ethanoic acid (b) $\mathrm{H}_{2} \mathrm{~S}$ (Hydrogen sulphide) (c) Propanone (d) $\mathrm{F}_{2}$ (Fluorine) [/solution]...
Read More →Based on the information given in this chapter,
[question] Question. Based on the information given in this chapter, match the following countries and the path democracy has taken in that country. [/question] [solution] Solution: (a) (ii) (b) (iv) (c) (iii) (d) (i) [/solution]...
Read More →What are the limitations of J.J
[question] Question. What are the limitations of J.J. Thomson’s model of the atom? [/question] [solution] Solution: According to J.J. Thomson’s model of an atom, an atom consists of a positively charged sphere with electrons embedded in it. However, it was later found that the positively charged particles reside at the centre of the atom called the nucleus, and the electrons revolve around the nucleus. [/solution]...
Read More →Use one of the following statements to complete the sentence:
[question] Question. Use one of the following statements to complete the sentence: Democracy in the international organisations requires that (a) The rich countries should have a greater say. (b) Countries should have a say according to their military power. (c) Countries should be treated with respect in proportion to their population. (d) All countries in the world should be treated equally. [/question] [solution] Solution: (d) All countries in the world should be treated equally. [/solution]...
Read More →Explain the nature of the covalent
[question] Question. Explain the nature of the covalent bond using the bond formation in $\mathrm{CH}_{3} \mathrm{Cl}$. [/question] [solution] solution: Atomic number of C, H & Cl are 6, 1 & 17 respectively. Their electronic configurations are Carbon – 2, 4 Hydrogen – 1 Chlorine– 2, 8, 7 As C need 4 electrons to complete its octet, H needs 1 electron to complete its duplet and Cl needs 1 electron to complete its octet. So, $\mathrm{C}$ share its 4 electron, one electron each with $3 \mathrm{H}$ ...
Read More →Compare the properties of electrons
[question] Question. Compare the properties of electrons, protons and neutrons. [/question] [solution] Solution: Electron (i) Electrons are present outside the nucleus of an atom. (ii) Electrons are negatively charged. (iii) The mass of an electron is considered to be negligible. Proton (i) Protons are present in the nucleus of an atom. (ii) Protons are positively charged. (iii) The mass of a proton is approximately 2000 times as the mass of an electron Neutron (i) Neutrons are present in the nu...
Read More →Which of the following statements is true about today’s world?
[question] Question. Which of the following statements is true about today’s world? (a) Monarchy as a form of government has vanished. (b) The relationship between different countries has become more democratic than ever before. (c) In more and more countries rulers are being elected by the people. (d) There are no more military dictators in the world. [/question] [solution] Solution: (c) In more and more countries rulers are being elected by the people [/solution]...
Read More →Which of the following does not lead to the spread of democracy?
[question] Question. Which of the following does not lead to the spread of democracy? (a) Struggle by the people. (b) Invasion by foreign countries, (c) End of Colonialism. (d) People's desire for freedom. [/question] [solution] Solution: (b) Invasion by foreign countries, [/solution]...
Read More →The graph of $y=p(x)$ are given in fig below,
[question] Question. The graph of $\mathrm{y}=\mathrm{p}(\mathrm{x})$ are given in fig below, for some polynomials $\mathrm{p}(\mathrm{x})$. Find the number of zeros of $\mathrm{p}(\mathrm{x})$, in each case. [/question] [solution] Solution: (i) Graph of $y=p(x)$ does not intersect the $x$-axis. Hence, polynomial $p(x)$ has no zero. (ii) Graph of $y=p(x)$ intersects the $x$-axis at one and only one point. Hence, polynomial $\mathrm{p}(\mathrm{x})$ has one and only one real zero. (iii) Graph of $...
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