PAKISTAN EXCEL ENGLISH SCHOOL
Topic-Chemical bonding
Name ----------------------Grade----------Date------------------
1-Which element doesn’t form stable ion with the same electronic configuration
as Neon?
A) Magnesium
B) Fluorine
C) Sodium
D)Chlorine
2-The electronic configuration of an ion was determined to be 2.8.8.
What could the identity of the ion be?
Ca 2+ S2-
A NO YES
B YES NO
C YES YES
D NO NO
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3-The table below shows the properties of four substances W,X,Y,Z.
SUBSTANCE MELTING BOILING CONDUCT CONDUCT
POINT POINT ELECTERICITY ELECTERICITY
/C /C WHEN SOLID WHEN LIQUID
W 3410 5930 YES YES
X 801 1413 NO YES
Y 3550 4830 NO NO
Z -91 98 NO NO
Use the information in the table to to identify the substance that is ionic
compound:
A) W B) X C) Y D) Z
3. Ca reacts with fluorine to form Calcium flouride, which statement describes
what happens to Ca atom in this reaction?
A) Calcium ions lose electrons to form positive charge.
B) Calcium ions gain three electrons to form positive ions.
C) Calcium ions gain two electrons to form positive ions.
D) Calcium atoms lose two electrons to form positive ions.
4. Atoms P and Q have electronic structure as shown in the diagram. They react
together to form a covalent compound.
2
(P) (Q)
What is the formula of the compound?
A) P₂Q₃ B) P ₃Q C) P ₃Q₂
D)PQ₄
5. The atom of element Z has 6 electrons in its outer shell. How would this
element react?
A) It shares two electrons with four from another atom to form two covalent
bonds.
B) It shares four electrons with four from another atom to form four
covalent bonds.
C) It shares four electrons with two from another atom to form two covalent
bonds.
D) It shares two electrons with two from another atom to form two covalent
bonds.
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6. CH₄,H₂0 and HCl are covalent compounds, which atoms in these compounds
don’t use all of their outer shell electrons in bonding ?
A) C and O
B) C and H
C) Cl and O
D) Cl and C
7. Which of the following molecules contains only single covalent bond?
A) N₂
B) F₂
C) O₂
D) CO₂
8. Which of the following statements about graphite and diamond are
incorrect?
1) They are allotropes of carbon.
2)They both conduct electricity.
3) They form different types of bonds within their structures.
4) They have both different uses.
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A) 2 and 3 B) 2 and 4 C) 1,3 and 4 D)2 and
9. Which statement correctly describes the structure of macromolecules?
A) Giant molecular crystal which is held together by weak intermolecular
forces.
B) Giant molecular crystal which is held together by strong intermolecular
forces.
C) Giant molecular crystal which is held together by weak metallic bonds.
D) Giant molecular crystal which is held together by strong covalent bonds.
E)
10. Statements 1,2 and 3 are about diamond and graphite.
1. They have atoms that form three equally strong bonds.
2. They are both formed from same element.
3. They each conduct electricity.
Which statement(s) is/are true?
A) 1 only B) 2 only C) 1 and 3 D) 1and 2
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11. In a water molecule, each hydrogen atom is bonded to the oxygen atom by
sharing a pair of electrons.
Why does an oxygen atom share two pair of electrons rather than just one pair?
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12) Describe how a Potassium atom become a Potassium ion?
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13) Solid Potassium chloride is poor conductor of electricity, when dissolved in
water it is a good conductor, Explain .
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14) The following is a list of the electron distributions of atoms of unknown
elements.
A) 2,5
B) 2,8,4
C) 2,8,8,2
D) 2,8,18,8
E) 2,8,18,8,1
F) 2,8,18,18,7
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Choose an element from the list for each of the following descriptions.
1) It is a noble gas.
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2) It is soft metal with low density
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3) It can form covalent compound with element A
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4) It has giant covalent structure similar to
diamond---------------------------------------------------------
5) It can form a negative ion of the type X 3-
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15. The question is about the structure and bonding in methane . A molecule of
methane is shown below
H
A) H C H
H
A) Give the formula of this methane molecules. How did you know?
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B) What type of bonding is found in methane?
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C) The bonding in methane can be shown using a dot and cross diagram.
Draw this dot and cross diagram.
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16. Complete the following table:
Type of Particles Electrical Electrical
structure present conductivity conductivity example
of solid of liquid
Ionic Positive and poor ………………. ……………
negative ions
Macromolecule Atoms of two poor poor ……………
different
elements in a
giant covalent
structure
Metallic ……………………. good ……………… copper
………………………
and………………
17.Diamond and graphite are different forms of the same element,
carbon.
Explain the following in terms of their structure .
A) Graphite is soft material which is used as lubricant.
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B) Diamond is a very hard material used for drilling and cutting.
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