http://www.icseguess.com/ GuessPaper – 2011 Class – IX Subject – (Chemistry) Set – I
Time – 1 ½ Hours
Full Marks – 80
Section I is compulsory. Answer any FOUR questions from Section II. Section – I [40 Marks] Answer all questions from this section. Question – 1. Answer the following questions: – (a) (b) (c) (d) (e) (f) (g) (h)
(i) (j) (k) (l)
(m) (n) (o) (p)
[2×20 = 40]
With reference to inter-conversion of matter, explain the meaning of the term vaporization and sublimation. Explain the change of state of matter on the basis of kinetic theory of matter with reference to solidification on cooling a liquid at its freezing point. What is meant by the term “Atomicity of a gas”. Name a gas which is diatomic. Explain briefly how you would obtain CO from a mixture of CO and CO2. Give one example each of two different types of homogeneous and heterogeneous mixtures. Name a non-met non-metallic allic element element which: which: (i) is a liquid liquid at ordinary ordinary temper temperatures atures (ii) (ii) is a conductor of electricity. XCl2 is the chloride of a metal X. State the formula of the sulphate and the hydroxide of the metal X. Write the formula for the following compounds: (i) sodium zincate (ii) copper (II) carbonate (iii) aluminium phosphate (iv) calcium silicate (v) magnesium nitride (vi) iron (III) sulphate. Give one reason why magnetizing a piece of steel is a physical change. Why silver nitrate solution is kept in coloured reagent bottles in the laboratory. How does an increase in temperature affect: (i) the solubility of NaCl (ii) the solubility of CaSO4 in water. Give reasons for the following: (i) table salt becomes moist and sticky during the rainy season (ii) a white powder forms on the surface of washing soda crystals which are left exposed to the air. Define the term: atomic number, mass number and electron. Ordinary chlorine gas has two isotopes: 35Cl17 and 37Cl17 in the ratio 3 : 1. Calculate the relative atomic mass (atomic weight) of chlorine. What is proton? What is the significance of the number of proton found in the atoms of each of the different elements? Write down the electronic configuration of: (i) 27X13 (ii) 35Y17.
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http://www.icseguess.com/ (q) (r) (s) (t)
What is meant by a Group in a Periodic Table. How many Groups are there in a Periodic Table. How many elements are there in Period 2. Name the elements of Period 2. What do the following symbols represent: 2H and H2. Explain their difference. Why is copper not used to prepare hydrogen by the action of dilute hydrochloric acid or dilute sulphuric acid on the metal.
Section – II (40 Marks) Answer ANY FOUR questions from this section. Question – 2. (a) Give a diagrammatic representation of the inter-conversion of the three states of matter with reference to ice as a solid state, water as a liquid state and steam as the gaseous (vapour) state. [3] (b) Define and explain the term melting point. Describe a simple experiment to determine the melting point of a solid. [3] (c) With the help of a neat labeled diagram, give a simple experiment to demonstrate the sublimation of iodine. What do you mean by the term ‘sublimate’. [4] Question – 3. (a) State and explain Boyle’s Law. [3] (b) Pressure on one mole of gas at s.t.p. is doubled and the temperature is raised to 546K. What is the final volume of the gas? [one mole of a gas occupies a volume of 22.4 litres at s.t.p.] [4] (c) How would you obtain oil from a mixture of oil and water. [3] Question – 4. (a) 2KClO3 + [MnO2] → 2KCl + 3O2(g) + [MnO2] – is a balanced equation. (i) State what ‘balanced equation’ is. (ii) Give a reason why the above equation is balanced. (iii) State why the compound MnO2 is written in the bracket. (b) Write balanced equations for the following word equations: (i) Potassium nitrate → Potassium nitrite + Oxygen Calcium + Water → Calcium hydroxide + Hydrogen Iron + Hydrochloric acid → Iron (II) chloride + Hydrogen. (c) CaCO3 + 2HCl (dil) → CaCl2 + H2O + CO2 (g) (i) State the information provided by the above chemical equation. (ii) State the information not conveyed by the above chemical equation.
[3] (ii) (iii) [3]
[4]
Question – 5. (a) What is ‘water of crystallization’? Name a crystalline salt which does not contain water of crystallization. [3] ------------------------------------------------------------------------------------------------------www.icseguess.com Other Educational Portals www.cbseguess.com | www.ignouguess.com | www.dulife.com | www.magicsense.com
http://www.icseguess.com/ (b)
(c)
A sample of waterweed was placed in water and exposed to sunlight. Bubbles of a gas are seen to form on the surface of leaves: [4] (i) Name the gas evolved. (ii) Name the process taking place. (iii) Give a balanced equation of the reaction which takes place during the process. Differentiate between unsaturated, saturated and supersaturated solutions. How would you convert a saturate solution to an unsaturated solution and vice versa. [3]
Question – 6. (a) Copy and complete the following table relating to the atomic structure of some elements. [4] Atomic Mass Number of Number of Number of Elements Number Number Protons Neutrons Electrons Beryllium 4 9 Fluorine 9 10 Sodium 12 11 Aluminium 27 13 Phosphorus 31 15
(b)
(c)
Elements X, Y, Z have atomic numbers 6, 9 and 12 respectively. Which one: (i) forms anion – negative ion; (ii) form cation – positive ion; (iii) has 4 elements in the outermost orbit. [3] 24 26 Mg12 and Mg12 are symbols of two isotopes of magnesium. Compare the atoms of these isotopes with respect to: [3] (i) the composition of their nuclei (ii) their electronic configuration. (iii) Give reason why the two isotopes of magnesium have different mass numbers
Question – 7. (a) What is the common feature of the electronic configuration of the elements at the end of period 2 and period 3? Are elements of group 7 likely to be metallic or non-metallic character? [3] (b) Write short notes on the following types of elements: – (i) alkali metals (ii) alkaline earth metals (iii) halogens (iv) noble gases. [3] (c) Name or state the following with reference to the elements of the first three periods of the periodic table. (i) A metalloid in period 2 and in period 3. (ii) The valency of elements in group IA. (iii) The nonmetallic element present in period 3 other than sulphur and chlorine. ------------------------------------------------------------------------------------------------------www.icseguess.com Other Educational Portals www.cbseguess.com | www.ignouguess.com | www.dulife.com | www.magicsense.com
http://www.icseguess.com/ (iv) An electrovalent compound formed between an alkali metal and a halogen. (v) A covalent compound formed between an element in period 1 and a halogen. (vi) The bridge elements of period 3 of group IA, IIA and IIIA.
[4]
Question – 8. (a) Account for the following facts: (i) Though lead is above hydrogen in the activity series, it does not react with dilute hydrochloric acid or dilute sulphuric acid. (ii) Potassium and sodium are not used to react with dilute hydrochloric acid or dilute sulphuric acid in the laboratory preparation of hydrogen. [3] (b) Place the metals calcium, iron, magnesium and sodium in order of their activity with water, placing the most active first. Write the equation for each of the above metals which react with water. [4] (c) Describe briefly, with equations, the Bosch Process for the large scale production of hydrogen. [3]
Paper Submitted By:
Name: Mr. M. P. Keshari Email Id:
[email protected] Telephone No. 09434150289
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