Structure of The Atom Question 1.(i) Calculate the number of electrons which will together weigh one gram.(ii) Calculate the mass and charge of one mole of electrons. Solution. Question 2.(i) Calculate the total number of electrons present in one mole of methane.(ii) Find (a) the total number and (b) the total mass of neutrons in 7 mg of 14C. (Assume that mass of a […]
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Some Basic Concepts of Chemistry Question 1.Calculate the molecular mass of the following :(i) H2o(ii) CO2(iii) CH4 Solution:(i) Molecular mass of H2O :2 × 1 + 1 × 16 = 18u(ii) Molecular mass of CO2 :1 × 12 + 2× 16 = 44 u(iii) Molecular mass of CH4 : 12 + 4 × 1 = 16 u Question 2.Calculate the mass percent of
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Probability (Ex – 16.3) Question 1.Which of the following cannot be valid assignment of probabilities for outcomes of sample spaceS = {⍵1, ⍵2, ⍵3, ⍵4, ⍵5, ⍵6, ⍵7} Solution:(a) Sum of probabilities = 0.1 + 0.01 + 0.05 + 0.03 + 0.01 + 0.2 + 0.6 = 1.00∴ Assignment of probabilities is valid.(b) Sum of
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Probability (Ex – 16.2) Question 1.A die is rolled. Let E be the event “die shows 4” and F be the event “die shows even number”. Are E and F mutually exclusive? Solution:An experiment consists of rolling a die.∴ S = {1, 2, 3, 4, 5, 6}E: die shows 4 = {4}F : die shows
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Probability (Ex – 16.1) In each of the following Exercises 1 to 7, describe the sample space for the indicated experiment. Question 1.A coin is tossed three times. Solution:When one coin is tossed three times, The sample space of the experiment is given by S = {HHH, HHT, HTH, THH, TTH, THT, HTT, TTT}. Question
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Statistics (Ex – 15.3) Question 1.From the data given below state which group is more variable, A or B? Solution:For Group A : Question 2.From the prices of shares X and Y below, find out which is more stable in value: Solution: Question 3.An analysis of monthly wages paid to workers in two firms A
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Statistics (Ex – 15.2) Find the mean and variance for each of the data in Exercises 1 to 5. Question 1.6, 7, 10, 12, 13, 4, 8, 12 Solution:Here xi = 6, 7, 10, 12, 13, 4, 8, 12∴ Σxi = 6 + 7 + 10 + 12 + 13 + 4 + 8 + 12 =
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Statistics (Ex – 15.1) Find the mean deviation about the mean for the data in Exercises 1 and 2. Question 1.4, 7, 8, 9, 10, 12, 13, 17 Solution:Mean of the given data is Question 2.38, 70, 48, 40, 42, 55, 63, 46, 54, 44 Solution:Mean of the given data is Question 3.13, 17, 16,
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Mathematical Reasoning (Ex – 14.5) Question 1.Show that the statementp: “If x is a real number such that x3 + 4x = 0, then x is 0″ is true by(i) direct method,(ii) method of contradiction,(iii) method of contrapositive. Solution:The given compound statement is of the form “if p then q”p: x ϵ R such that x3 + 4x = 0q:
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Mathematical Reasoning (Ex – 14.4) Question 1.Rewrite the following statement with “if-then” in five different ways conveying the same meaning. If a natural number is odd, then its square is also odd. Solution:(i) A natural number is odd implies that its square is odd.(ii) A natural number is odd only if its square is odd.(iii) For a natural
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