SUMMER HOLIDAY H.W.
Session 2015 – 2016
Subject : Chemistry Class : XI
2.
1. Arrange the following in order of increasing masses :
(a) one atom of silver (b) one mole of calcium (c) one mole of O2
(d) 1022atoms of carbon
Which of the following contains the maximum number of moles
(a) 224 cm3 of hydrogen at STP (b) 3.6 g of water
3.
(c) 112 cm3 of chlorine at STP (d) 12 g of carbon
2. 500 mL of a 0.250 M Na2SO4 solution was added to an aq. solution of 15 g BaCl2 resulting in the formation of BaSO4 precipitate. Calculate the amount of BaSO4 formed. Which one of these is the limiting reagent. (mol mass BaCl2 =208 g mol–1 ; BaSO4 =233 g mol–1)
What weight of pyrolusite ,MnO2 , must react with HCl to obtain enough chlorine to fill a container of 10 L volume at 273 K and 1 atm pressure ?
MnO2 + 4HCl →
(molecular mass of MnO2 =87 g mol–1)
MnCl2 + 2 H2O + Cl2
4. The density of a liquid metal is 6.1 g cm–3 . What is the volume occupied by 100 atoms of the
2.
3.
5. metal if the mass of one atom is = 1.16 × 10–22 g ) .
A compound containing Na, S H and O gave the following results on analysis : Na=14.28% ,
S=9.92% , H= 6.20%.Deduce the molecular formula of the compound if all the H atoms in the salt are in combination with O as water of crystallization.
6. Solve the NCERT In Text and Exercise problems
UNIT-2 (Structure of Atom)
1. (a) The maximum number of 3d electron that can have spin quantum number
+1/2 is ____ .
(b) Among X-rays ,visible rays ,infra-red rays and micro waves ,which one has the highest frequency.
(c) What is the significance of Pauli's Exclusion principle ?
Arrange the orbitals 2s , 3p, 4s, 2p, 3d , 4p in the order of increasing energy .
Write the electronic configuration of Mn (atomic number of Mn=25).
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4. The ground state energy of hydrogen electron is –1312 kJ/mol.What will be the energy of the electron when it is excited to the second energy level ? Calculate the wave-length of radiation required to excite the hydrogen electron from the first to thesecond energy level.
Given : h = 6.6×10–34Js ; Avogadro's number = 6.02×1023 and
5. velocity of light =3×108 m/s.
An orbital is represented by the quantum numbers : n = 2 , l = 1 , m = 0 ; what are the quantum number values of another orbital with the same energy.
What is the designation of this orbital. How many electrons this orbital can accomodate?
6. (a) Which of the following are isoelectronic species: K+, Na+, Ca2+, F–, Mg2+, O2–
(b) Write the configuration of the following ions : H – ,
(c) What is the lowest n value that allows g orbitals to exist ?
7. Write down the electronic arrangement of the elements from atomic No. 1 to 110.
8. Solve the NCERT In Text and Exercise problems
Questions for PSA
(1) Avogadro’s number represents the number of atoms in
(a) 12g of C12 (b) 320g of sulphur
(c) 32g of oxygen (d) 12.7g of iodine
(2) The number of moles of carbon dioxide which contain 8 g of oxygen is
(a) 0.5 mol (b) 0.20 mol
(c) 0.40 mol (d) 0.25 mol
(3) The total no of ions present in 111 g of cacl2 is
(a) One mole (b) Two mole
(c) Three mole (d) Four moles
(4) Which of the following weighs the most ?
(a) one g-atom of nitrogen (b) One mole of water
(c) One mole of sodium (d) One molecule of H2So4
(5) 5.0 litre of 0.4 M H2SO4 Contains-
(a) 2.0 Mole Of H2So4 (b) 0.4 mole H2So4
(c) 5.0 mole H2So4 (d) 2.0 moles H2O
(6) A symbol not only represents the name of the element but also represents-
(a) its atomic no. (b) 1 gm-atom
(c) its atomicity (d) Reactivity.
(7) Which has maximum number of atoms ?
(a) 24g of c (12) (b) 56g of Fe (56)
(c) 27g of Al (27) (d) 108g of Ag (108)
(8) Number of atoms of oxygen present in 10.6g Na2Co3 will be-
(a) 6.02 × 1022 (b) 12.04 × 1022
(c) 1.806 × 1023 (d) 31.80 × 1023
(9) The maximum no. of molecules is present in
(a) 15 L of H2 gas at S.T.P (b) 5 L of N2 gas at S.T.P
(c) 0.5 g of H2 gas (d) 10 g of O2 gas.
(10) The number of g-atom of oxygen in 6.02 × 1024 CO molecules is
(a) 1 (b) 0.5
(c) 5 (d) 10
Na+ , F–
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