1st Mid-Term
General Chemistry (CHEM-104)
Student name:
Answer the following questions:
I. Put circle around the correct answer of the following questions (20 marks) :
1. The chemical bonding in NaCl is :
(a) covalent bond
(b) ionic bond
(c) coordinate covalent bond
(d) metallic bond
2. Covalent bond is taking place between:
(a) atoms of two non-metals
(b) atoms of metal and non-metal
(c) atoms of two metals
(d) All answers are wrong
3. The electron configuration of phosphorus atom is:
(a) 1s2 2s22p6 2d10 3s23p33d6
(b) 1s2 2s22p63s23p3
(c) 1s2 1p6 2s22p5
(d) All answers are wrong
4. The electron configuration of sulfur atom (atomic number = 16) is:
(a) 1s2 2s22p6 3p6
(b) 1s2 2s22p63s6
(c) 1s2 2s22p63s23p4
(d) All answers are wrong
5. Different elements:
(a) are similar in mass, size, and shape
(b) show the same physical characteristics
(c) show the same chemical characteristics (d) are different in mass, size, and shape
6. Isotopes are known as atoms that have:
(a) the same number of protons
(b) different number of electrons
(c) the same number of neutrons
(d) All answers are wrong
7. The oxidation number of phosphorus in AlPO4:
(a)
-5
(b) -6
(c)
+5
(d) +6
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8. The chemical bonding in CHBr3 is :
(a) polar covalent bond
(b) ionic bond
(c) non-polar covalent bond
(d) metallic bond
9. The nucleon number of
(a) 14
6C
14
atom is:
(b) 6
(c) 8
(d) 20
10. Ions of metals are always positive because:
(a) the metals tend to gain electrons
(b) the metals tend to lose electrons
(c) the metals does not lose or gain electrons
(d) All answers are wrong
Q2. Write-down the class of the chemical reaction in the following table:
Q3. What are the mole fractions of CH3OH and H2O in a solution prepared by
dissolving 1.20 g of methyl alcohol in 16.8 g of water ?
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Q5. In USA, drinking water cannot contain more than 5 x 10-4 mg of mercury per
gram of sample. Calculate the concentration in parts per million parts (PPM)?
Atomic weight of some atoms:
C= 12
H= 1
O= 16
With my best wishes
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