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Topic 4: Chemical bonding

20 . Molecular structures and shapes: Recognizing bond and molecular polarity by structures
1. Which diagram best represents a polar molecule?
1) 2) 3) 4) + -

Cl2 HCl H2 Na Cl

2. Which molecule is polar?

H
I
1) H – S 2) H – C – H 3) O = C = O 4) N = N
I I
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H H

H
3. Which molecule is polar? I

1) Li – Cl 2) H – N – H 3) Cl – Cl 4) H-C-H
I I
H H

4. Which structural formula represents a polar molecule?
1) H – H 2) Na – H 3) H – Br 4) O = O

5. Which structural formula represents a nonpolar symmetrical molecule?
Cl Teacher Preview Copy
1) Na – Cl 2) O = C = O 3) H – I 4) O
H H

6. Which structural formula is linear and nonpolar?

H
1) H – Cl I 3) H – N – H 4) Cl – Cl
2) H – C – H
I I

H H

7. The structure of which molecule is nonpolar with polar covalent bonds?
O
I 2) H H 3) N Ξ N 4) H – F
1) Cl – C – Cl
I

Cl

8. Which formula has a tetrahedral shape and is symmetrical?
F

1) H – N – H 2) S I
3) F – C – F
4) H – H
I

I

H H H F

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