Chemistry assignment

Term: 2019 Summer

Mid term test

Name: ___________________________ Time: _______________ Total: _________

1. Choose the right answer: (2points each, 6 points)

(1)Which of the substances below is not a compound?

A. Sugar

B. Water

C. Chlorine

D. Carbon dioxide Answer:_________________

(2)In the periodic a group of family is described as:

A. Horizontal rows

B. Diagonal rows

C. Vertical columns

D. None of the above Answer:_________________

(3)In what period does iodine belong to: Answer:_________________

A. 5 B. 4 C. 3 D. 2

2. Write ground-state electron configurations for these ions, which play important roles in biochemical processes in our bodies: (2points each, 16 points)

(a) Na+ Answer:_________________

(b) Mg2+ Answer:_________________

(c) Cl - Answer:_________________

(d) K+ Answer:_________________

(e) Ca2+ Answer:_________________

(f) Fe2+ Answer:_________________

(g) Cu2 + Answer:_________________

(h) Zn2+ Answer:_________________

3.Classify these bonds as ionic, polar covalent, or co-valent: (2points each, 8 points)

(a) the Si-Si bond inCl3SiSiCl3, Answer:_________________

(b) the Si-Cl bond in Cl3SiSiCl3 Answer:_________________

(c) the Ca-F bond in CaF2 Answer:_________________

(d) the N-H bond in NH3 Answer:_________________

4. Complete and balance the following equations(3points each, 15 points)

(a) Sr + Se →

(b) Ca + H2 →

(c) Li + N2 →

(d) Al + S →

(e) HCOOH + CH3OH →

5. Name the following compounds: (3points each, 15 points)

H

3

C

C

H

CH

3

H

2

C

H

2

C

CH

3

(a)

H

3

C

H

2

C

H

C

H

2

C

CH

3

(b)

H

2

C

H

2

C

CH

3

(c)

H

3

C

C

H

C

2

H

5

C

H

C

H

CH

3

CH

3

CH

3

H

2

C

H

C

C

H

H

2

C

CH

3

(d)

Br

H

3

C

C

C

H

2

C

CH

3

(e)

Answer:_________________

Answer:_________________

Answer:_________________

Answer:_________________

Answer:_________________

6. Draw three resonance structures for the chlorate ion, ClO3- . Show formal charges. (10 points)

7. Draw all possible isomers for the molecule C3H5Br. (10 points)

8. Suggest two chemical tests that would help you distinguish between these two compounds: (10 points)

(a) CH3CH2CH2CH2CH3 (b) CH3CH2CH2CH=CH2

9. Diethyl ether (CH3CH2OCH2CH3)has a boiling point of 34.5 0C, and1-butanol (CH3CH2CH2CH2OH) has a boiling point of 117 0C. (10 points)

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H

3

C

C

H

CH

3

H

2

C

H

2

C

CH

3

(a)

H

3

C

H

2

C

H

C

H

2

C

CH

3

(b)

H

2

C

H

2

C

CH

3

(c)

H

3

C

C

H

C

2

H

5

C

H

C

H

CH

3

CH

3

CH

3

H

2

C

H

C

C

H

H

2

C

CH

3

(d)

Br

H

3

C

C

C

H

2

C

CH

3

(e)