ICSE CHEMISTRY - PRACTICE PAPER 17

ICSE CHEMISTRY - PRACTICE PAPER 17

 Chapters : Periodic Table and Chemical Bonding

a)  Name/Give a term/State the following.

1.        A covalent compound which when dissolved in water behaves like an electrovalent compound.

2.        A bond formed by the transfer of electrons from an electropositive element to an electronegative element.

3.        The atom bearing two lone pairs of electrons in water molecule.

4.     A covalent compound in which the shared pair of electrons are unequally distributed between the atoms.

5.               The weak intermolecular force of attraction existing in covalent compounds.

6.      An element which has 1,2 or 3 valence electrons and lose electrons to form cations.

7.      An element which has 4,5,6 or 7 electrons in its valence shell and accept electrons to attain stable electronic configuration.

8.      A covalent compound which when dissolved in water behaves like an electrovalent compound.

9.      A polar covalent compound with one lone pair of electrons on Nitrogen atom.

10.  A non polar covalent molecule of identical atoms with one triple bond.

11.  A polar covalent compound which combines with H⁺ and forms Hydronium ion.

12.  The charged particle which attract one another in the formation of an electrovalent compound.

13.  A bond formed by the transfer of electrons from an electropositive element to an electronegative element.

14.  A bond formed by a shared pair of electrons with both electrons coming from the same atom.

  b) Classify the following as Oxidation or Reduction reactions.

i)   Fe --> Fe²⁺

ii)  Cl^{–   -->} Cl

iii)  O     --> O^2–

iv)   Na    -->   Na⁺

c) A, B, C and D are the elements with valence electrons 7,2, 4 and 1 respectively. Answer the following:

i)  Nature of the bonding between C and A.

ii) Formula of the compound between B and A.

iii) Nature of the bonding between D and A. and draw the electron dot structure of that compound.

iv)       If A is a non metal containing diatomic molecule then write balanced equation for the reaction between A and B.

d) Give reasons

1.      Electrovalent compounds are crystalline solids and have high boiling point and melting point.

2.      Electrovalent compounds are non volatile.

3.      Electrovalent compounds conduct electricity in fused or aqueous solution state but do not in solid state

		IA	IIA											IIIA		IVA		VA		VIA		VIIA	0
		1	2	3	4	5	6	7	8	9	10	11	12	13		14		15		16		17	18
1		A																					D
2		C	E											Q				W		X		Z
3		G	H											R		T				Y			J
4		M

i) State the number of shells present in ‘C’.

ii) Write the valencies of M, E and X.

iii) Formula of the compound between ‘E’ and ‘X’.

iv) What type of bonding is possible between A and Z.

v) Write the formula of the oxide of G.

vi) Which one has the highest electronegativity among the elements belonging to Period 3. (from the given table).

vi) Write the balanced equation for the reaction between E and Y.

vii) Identify the metalloids in the table.

d) Give reason why:

i) Electronegativity decreases in a group.

ii) Atomic radium decreases a period