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Physics - 1

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Choose the Correct Option 1 Origin of the word 'Science' is from (a) French word 'Scientia' (b) Greek word 'Scientia' (c) Latin word 'Scientia', which means 'scientific' (d) Latin word 'Scientia', which means 'to know' Click here to Check Answer Answer (d) 2 Origin of the word 'Physics' is from (a) French word 'Fusis' (b) Latin word 'Fusis' (c) Greek word 'Fusis', which means 'Nature' (d) Greek word 'Fusis', which means 'Physical' Click here to Check Answer Answer is (c) 3 Which of the following statements is/are correct? (a) Universal law of gravitation is an assumption or hypothesis (b) Universal law of gravitation can be proved (c) Universal law of gravitation can be verified (d) Both (a) and (c) click here to check answer Answer is (d) 4 A theory proposed to explain observed phenomena is (a) Postulate (b) ...
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Chemistry – 1

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1 The oxidation number of carbon in CH₂O is - 2 +2 0 +4 click here We have x + 2(+1) + (–2) = 0. This gives x = 0. 2 The value of Avogadro constant is 6.022 × 10²³ 6.022 × 10²³ mol⁻¹ 6.022 × 10²³ atoms 6.022 × 10²³ molecule mol⁻¹ click here answer is 6.022 × 10²³ mol⁻¹ 3 The largest number of molecules is in 36 g of water 28 g of carbon monoxide 46 g of ethyl alcohol 54 g of nitrogen pentoxide click here Amount of water, M/M = 36 g / 18 g mol⁻¹ = 2 mol ; Amount of carbon monoxide 28 g / 28 g mol⁻¹ = 1 mol ; Amount of ethyl alcohol=46 g / 46 g mol⁻¹ = 1 mol ; Amount of nitrogen pentoxide = 54 g / 108 g mol⁻¹ = 0.5 mol ; Larger the amount of substance, larger the number of molecules. Ans : 36 g of water 4 The oxidation state of nitrogen in N₃H is - 1/3 - 1 1/2 2 click here The oxidation of N in N3H may be computed from the expression 3x + 1 = 0. This gives x = - ⅓. 5 The oxidation state of nickel in Ni(CO)₄ is ...
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