Chapters

Structure of Atom , Classification of Elements and Periodicity in Properties

Time Allotted:  45 Minutes

Test Date:  21-Jun-2012

Q1. Use the following information to answer the next question Dalton’s atomic model had some shortcomings. J.J. Thomson made an improvement to Dalton’s model. Which of the following statements is true regarding Thomson’s atomic model? A : Thomson’s atomic model suggests that all matter is made up of atoms. B : Thomson’s atomic model infers the existence of an electron and a nucleus. C : Thomson’s atomic model suggests that atoms are indivisible and indestructible entities. D : Thomson’s atomic model infers that an electron moves around the nucleus in a definite orbit.

Q2. Which of the following elements has the largest size? A : Fluorine B : Neon C : Chlorine D : Argon

Q3. The three particles, electrons, protons, and neutrons are called A : elementary particles B : indivisible particles C : charged particles D : atomic particles

Q4. Which of the following classes of elements has the maximum tendency to accept electrons? A : Alkali earth metals B : Transition metals C : Halogens D : Inert gases

Q5. Thallium is a highly toxic p block element. Thallium sulfate is used as a rodent killer, while thallium oxide is used for producing high refractive index glasses. Its electronic configuration is [m] 4f145d106s26p1. In the electronic configuration of thallium, m denotes which noble gas? A : Radon B : Argon C : Xenon D : Krypton

Q6. Which of the following alkaline earth metals has the largest atomic radius? A : Beryllium B : Magnesium C : Calcium D : Strontium

Q7. What is the value of Planck’s constant? A : 6.99 × 10−39 Js B : 6.86× 10−36 Js C : 6.63× 10−34 Js D : 6.14 × 10−33 Js

Q8. Which of the following elements has the highest electron affinity? A : Fluorine B : Chlorine C : Bromine D : Iodine

Q9. The energy of an electron in the first Bohr orbit of a hydrogen atom is −13.6 eV. What is the energy of electrons in the excited state in the second Bohr orbit of hydrogen atom? A : −6.8 eV B : −3.4 eV C : +3.4 eV D : +6.8 eV

Q10. Which of the following elements has the highest electron affinity? A : Carbon B : Nitrogen C : Oxygen D : Fluorine

Q11. What is the radius of the second orbit of He+ ion? A : 0.265 Å B : 0.529 Å C : 1.058 Å D : 2.116 Å

Q12. On moving from left to right in a period, the atomic radii A : increases regularly B : decreases regularly C : first decreases and then increases D : first increases and then decreases

Q13. Which of the following orbital diagrams violates both Pauli Exclusion Principle and Hund’s rule of Maximum Multiplicity? A : 2s2, 2px2,2py1 B : 2s2, 2px2,2py2 C : 2s1, 2px1,2py1,2pz1 D : 2s2, 2px1,2py1,2pz1

Q14. In the long form of periodic table, the elements having similar properties A : recur after a fixed number of elements B : recur after every eight elements C : form horizontal rows D : form vertical groups

Q15. How many unpaired electrons are there in the ground state electric configuration of selenium? A : 4 B : 3 C : 2 D : 0

chemistry XI chapter 1 practice questions

CHEMISTRY                        CHAPTER  1                                     PRACTICE QUESTIONS

Q1. .

Iodine reacts with chlorine to form two inter halogen compounds, iodine monochloride and iodine trichloride, according to the following reaction: I2 + Cl2→ICl + ICl3 In the solid state, iodine trichloride dimerizes and forms a dimer I2Cl6. The solid decomposes to give ICl and Cl2 when heated. The reaction is as follows: ICl3 →ICl + Cl2.

How many molecules of ICl₃ are formed when 127 g of iodine is completely reacted with 71 g of chlorine?

Q2.

Use the following information to answer the next question.Calcium carbonate (CaCO3) decomposes to produce calcium oxide and carbon dioxide according to the following reaction: CaCO3 → CaO + CO2

How many molecules of carbon dioxide can be obtained by the decomposition of 24 g of calcium carbonate at STP?

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Q3.

Use the following information to answer the next questionAmmonia is oxidized, catalytically, into nitric oxide in the presence of platinum. The reaction is as follows: NH3 + O2 → NO + H2O

What amount of nitric oxide can be obtained by reacting 12 g of oxygen with 12 g of ammonia?

Q4.

Use the following information to answer the next question.When sulfides of copper are roasted, poisonous sulfur dioxide (SO2) gas is produced according to the following reaction: Cu2S + O2 → 2Cu + SO2. This sulfur dioxide, when released into atmosphere, gets converted into sulfuric acid.

What amount of sulfur dioxide will be released when 39.5 g of copper sulfide is roasted in excess of oxygen?

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Q5.

Use the following information to answer the next questioNitrogen reacts with hydrogen to give ammonia according to the following reaction: N2 (g) + 3H2 (g) → 2NH3 (g)

What amount of hydrogen is required to react completely with 6 grams of nitrogen?

Q6.

Use the following information to answer the next question.Citral (C10H16O) is a major constituent of the oil of lemongrass. It is an aroma compound, which is used in perfumeries for its citrus effect. It is also used as a flavour. The molecular mass of citral is 152 gmol-1.

What is the mass ratio of oxygen to carbon in citral?

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Q7.

What quantity of calcium phosphate [Ca₃ (PO₄)₂] will contain 12 × 10²⁴ atoms of oxygen?

Q8.

The formation of water is an exothermic reaction as it produces a tremendous amount of energy. It is also an example of combustion reaction, wherein a substance combines with oxygen. Hydrogen reacts with oxygen to form water in the following manner: 2H2 + O2 → 2H2O + Energy

How many moles of water are obtained when four moles of hydrogen react with two moles of oxygen?

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Q9.

A particular chemical compound contains 5 per cent hydrogen, 60 per cent oxygen, and 35 per cent nitrogen. This compound is commonly used as a fertilizer. Its molecular mass is 80 gmol−1.

The number of atoms of nitrogen in the molecular formula of the compound is

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Q10.

A chemical compound contains 18 per cent cobalt, 5.96 per cent nickel, and 76.04 per cent arsenic. The number of atoms of arsenic, in the empirical formula of the compound is

Q11.

The mass (in grams) of one mole of atoms in a monatomic element is referred to as the gram atomic mass of that element.

Which of the following quantities weighs the maximum?

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Q12.

What is the percentage of sulfur in sulfuric acid (H₂SO₄)?

Q13.

Chloromethane (CH3Cl) is a clear and colourless gas that has a faint and sweet odour. This is noticeable only at toxic levels.

What is the percentage of chlorine in chloromethane?

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Q14.

Lead nitrate reacts with sodium iodide to give lead iodide and sodium nitrate in the following manner: Pb(NO3)2 + 2NaI → PbI2 + 2NaNO3

What amount of sodium nitrate is obtained when 30 g of lead nitrate reacts with 30 g of sodium iodide?

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Q15.

Sulfur dioxide reacts with oxygen to form sulfur trioxide in the following manner: 2SO2 + O2 → 2SO3

If 0.5 mole of sulfur dioxide is mixed with 0.5 mole of oxygen, then how many moles of sulfur trioxide can be obtained?

CATHODE RAY EXPERIMENT

http://www.youtube.com/watch?v=4QAzu6fe8rE

Some important topics related to co-ordination compounds

1. Nomenclature
2. terms related to co-ordination compounds
3. Isomerism
4. splitting of d- orbitals(diagrams) for octahedral and tetrahedral geometries.
5. How to find out Hybridizations