1. Second exam

2. 1-Which of the following pressure units has the largest value?
Second exam
1-Which of the following pressure units has the largest value? 
a)765 torr b) 1.00 atm c) 595 mmHg d) 167 Pa
a- 765/760 = atm
b- 1 atm
c- 595/760=0.78 atm
d- 167 / 1.01 x 105 = atm

3. 1-Which of the following pressure units has the largest value?
Second exam
1-Which of the following pressure units has the largest value? 
a)765 torr b) 1.00 atm c) 595 mmHg d) 167 Pa
2- A sample of oxygen occupies 6.33 liters under a pressure of 1240 mmHg at 25°C. What volume would it occupy at 25°C if the pressure was decreased to atm?
a) 23.6 L b) 12.7 L c) 32.1 L d) L
V1= 6.33 L , P1= 1240 mmHg = 1240 / 760= 1.63 atm, P2=0.96 atm, V2= ?, T1=T2
P1 V1 = P2 V2
1.63 x 6.33 = 0.96 x V2
V2 = / 0.96 = L

4. 1-Which of the following pressure units has the largest value?
Second exam
1-Which of the following pressure units has the largest value? 
a)765 torr b) 1.00 atm c) 595 mmHg d) 167 Pa
2- A sample of oxygen occupies 6.33 liters under a pressure of 1240 mmHg at 25°C. What volume would it occupy at 25°C if the pressure was decreased to atm?
a) 23.6 L b) 12.7 L c) 32.1 L d) L
3- What is the pressure of 3.45×10-3 mol gas in a 0.1L flask at 21.2°C? 
a) 0.99 atm b) 0.83 atm c) atm d) 0.5 atm
n= 3.45×10-3 mole, T= 21.2 °C= =294.2 K, V= 0.1L, P= ?
PV=nRT
P= nRT/V
= 3.45×10-3 x x / 0.1
= 0.83 atm

5. 1-Which of the following pressure units has the largest value?
Second exam
1-Which of the following pressure units has the largest value? 
a)765 torr b) 1.00 atm c) 595 mmHg d) 167 Pa
2- A sample of oxygen occupies 6.33 liters under a pressure of 1240 mmHg at 25°C. What volume would it occupy at 25°C if the pressure was decreased to atm?
a) 23.6 L b) 12.7 L c) 32.1 L d) L
3- What is the pressure of 3.45×10-3 mol gas in a 0.1L flask at 21.2°C? 
a) 0.99 atm b) 0.83 atm c) atm d) 0.5 atm
4- What is the mass of nitrogen gas (M=28 g/mol) in 500 mL flask at STP?
a) g b) g c) g d) g

6. V= 500 ml= 500/1000= 0.5L, T= 273K, P= 1 atm, Mwt= 28 g/mol PV= nRT
Second exam
4- What is the mass of nitrogen gas (M=28 g/mol) in 500 mL flask at STP?
a) g b) g c) g d) g
V= 500 ml= 500/1000= 0.5L, T= 273K, P= 1 atm, Mwt= 28 g/mol
PV= nRT
n= PV/RT
= 1 x 0.5 /( x 273)
= mol
Mass = n x molar mass
= x 28 = g

7. 1-Which of the following pressure units has the largest value?
Second exam
1-Which of the following pressure units has the largest value? 
a)765 torr b) 1.00 atm c) 595 mmHg d) 167 Pa
2- A sample of oxygen occupies 6.33 liters under a pressure of 1240 mmHg at 25°C. What volume would it occupy at 25°C if the pressure was decreased to atm?
a) 23.6 L b) 12.7 L c) 32.1 L d) L
3- What is the pressure of 3.45×10-3 mol gas in a 0.1L flask at 21.2°C? 
a) 0.99 atm b) 0.83 atm c) atm d) 0.5 atm
4- What is the mass of nitrogen gas (M=28 g/mol) in 500 mL flask at STP?
a) g b) g c) g d) g

8. 5- What is the density of oxygen gas (M= 32 g/mol) at STP?
Second exam
5- What is the density of oxygen gas (M= 32 g/mol) at STP?
a) 1.64 g/L b) 2.91 g/L c) 1.43 g/L d) 1.15 g/L
Mwt = 32 g/mol, T=273 K, P= 1 atm,

9. 5- What is the density of oxygen gas (M= 32 g/mol) at STP?
Second exam
5- What is the density of oxygen gas (M= 32 g/mol) at STP?
a) 1.64 g/L b) 2.91 g/L c) 1.43 g/L d) 1.15 g/L
6- A mixture of gases contains 6.0 mol of H2 gas and 2.5 mol of He gas. If the total pressure is 1.15 atm, calculate the partial pressure of the H2 gas. 
a) 1.06 atm b) atm c) 2.12 atm d) 1.41 atm
nH2= 6 mol, nHe = 2.5 mol, PT = 1.15 atm, PH2 = ?

10. 5- What is the density of oxygen gas (M= 32 g/mol) at STP?
Second exam
5- What is the density of oxygen gas (M= 32 g/mol) at STP?
a) 1.64 g/L b) 2.91 g/L c) 1.43 g/L d) 1.15 g/L
6- A mixture of gases contains 6.0 mol of H2 gas and 2.5 mol of He gas. If the total pressure is 1.15 atm, calculate the partial pressure of the H2 gas. 
a) 1.06 atm b) atm c) 2.12 atm d) 1.41 atm
7- A mixture of 3 mol N2 gas and 4 mol O2 are in 2 L flask at 300 K, what is the total pressure?
a) 57.4 atm b) 86.1 atm c) atm d) atm
nN2= 3 mol, nO2 = 4 mol, V = 2 L, T= 300K, PT = ?
Where n = nA + nB

11. 5- What is the density of oxygen gas (M= 32 g/mol) at STP?
Second exam
5- What is the density of oxygen gas (M= 32 g/mol) at STP?
a) 1.64 g/L b) 2.91 g/L c) 1.43 g/L d) 1.15 g/L
6- A mixture of gases contains 6.0 mol of H2 gas and 2.5 mol of He gas. If the total pressure is 1.15 atm, calculate the partial pressure of the H2 gas. 
a) 1.06 atm b) atm c) 2.12 atm d) 1.41 atm
7- A mixture of 3 mol N2 gas and 4 mol O2 are in 2 L flask at 300 K, what is the total pressure?
a) 57.4 atm b) 86.1 atm c) atm d) atm
8- What is the wavelength (λ) of radiation that has a frequency (υ) of 1.0 x 1014 Hz?
a) 5x10-3 cm b) 1x10-4 cm c) 3x10-4 cm d) 1x10-6 cm

12. a) 5x10-3 cm b) 1x10-4 cm c) 3x10-4 cm d) 1x10-6 cm
Second exam
8- What is the wavelength (λ) of radiation that has a frequency (υ) of 1.0 x 1014 Hz?
a) 5x10-3 cm b) 1x10-4 cm c) 3x10-4 cm d) 1x10-6 cm
V= 1.0  1014 s-1 , λ=?
c = λν
λ=c/v
= 3x108 /(1.0  1014 )
= 3.0 x10-6 m
= 3.0 X10-4 cm

13. 5- What is the density of oxygen gas (M= 32 g/mol) at STP?
Second exam
5- What is the density of oxygen gas (M= 32 g/mol) at STP?
a) 1.64 g/L b) 2.91 g/L c) 1.43 g/L d) 1.15 g/L
6- A mixture of gases contains 6.0 mol of H2 gas and 2.5 mol of He gas. If the total pressure is 1.15 atm, calculate the partial pressure of the H2 gas. 
a) 1.06 atm b) atm c) 2.12 atm d) 1.41 atm
7- A mixture of 3 mol N2 gas and 4 mol O2 are in 2 L flask at 300 K, what is the total pressure?
a) 57.4 atm b) 86.1 atm c) atm d) atm
8- What is the wavelength (λ) of radiation that has a frequency (υ) of 1.0 x 1014 Hz?
a) 5x10-3 cm b) 1x10-4 cm c) 3x10-4 cm d) 1x10-6 cm

14. Second exam
9- Calculate the volume of O2 (in L) required for the complete combustion of 7.64 L of C2H2 measured at the same temperature and pressure?
a) 19.1 L b) 9.1L c) 21.6L d) 14.1 L
From equation
2 mol C2H mol O2
2L C2H L O2
7.64 L C2H ? L O2
5 x 7.64 = 2 x ?
Volume of O2 = 5 X 7.64 / 2 = 19.1 L X

15. Second exam
9- Calculate the volume of O2 (in L) required for the complete combustion of 7.64 L of C2H2 measured at the same temperature and pressure?
a) 19.1 L b) 9.1L c) 21.6L d) 14.1 L
10-If the frequency (υ) of radiation is 1.00 x 108 Hz, what is the energy (E) of this radiation?
a) 6.63 x J b) 6.63 x J c) 6.63 x J d) 6.63 kJ
E= x x 1 X 108
= x 10-26

16. Second exam
9- Calculate the volume of O2 (in L) required for the complete combustion of 7.64 L of C2H2 measured at the same temperature and pressure?
a) 19.1 L b) 9.1L c) 21.6L d) 14.1 L
10- If the frequency (υ) of radiation is 1.00 x 108 Hz, what is the energy (E) of this radiation?
a) 6.63 x J b) 6.63 x J c) 6.63 x J d) 6.63 kJ
11- What is the energy of radiation after transition of an electron from n = 3 to n = 2 in the hydrogen atom? (The Rydberg constant for H atom = 2.18  J)
a) 3.03 x J b) 3.03  J c) 3.03  J d) 2.18  J

17. Second exam
11- What is the energy of radiation after transition of an electron from n = 3 to n = 2 in the hydrogen atom? (The Rydberg constant for H atom = 2.18  J)
a) 3.03 x J b) 3.03  J c) 3.03  J d) 2.18  J

18. Second exam
9- Calculate the volume of O2 (in L) required for the complete combustion of 7.64 L of C2H2 measured at the same temperature and pressure?
a) 19.1 L b) 9.1L c) 21.6L d) 14.1 L
10- If the frequency (υ) of radiation is 1.00 x 108 Hz, what is the energy (E) of this radiation?
a) 6.63 x J b) 6.63 x J c) 6.63 x J d) 6.63 kJ
11- What is the energy of radiation after transition of an electron from n = 3 to n = 2 in the hydrogen atom? (The Rydberg constant for H atom = 2.18  J)
a) 3.03 x J b) 3.03  J c) 3.03  J d) 2.18  J

19. a) from n = 1 to n = 4 b) from n = 1 to n = 2
Second exam
12- Which of the following electron transitions would absorb the lowest energy by the hydrogen atom?
a) from n = 1 to n = b) from n = 1 to n = 2
c) from n = 1 to n = d) from n = 1 to n = 6
13- Calculate the wavelength associated with a beam of neutrons moving at 7.0 x 102 m/s? (The mass of a neutron is x kg).
a) nm b) nm c) nm d) nm
m= x kg, u= 7.0 x 102 m/s

20. a) from n = 1 to n = 4 b) from n = 1 to n = 2
Second exam
12- Which of the following electron transitions would absorb the lowest energy by the hydrogen atom?
a) from n = 1 to n = b) from n = 1 to n = 2
c) from n = 1 to n = d) from n = 1 to n = 6
13- Calculate the wavelength associated with a beam of neutrons moving at 7.0 x 102 m/s? (The mass of a neutron is x kg).
a) nm b) nm c) nm d) nm
14- The volume of a sample of nitrogen is 7.20 liters at 35°C and atm. What volume will it occupy at STP?
a) 8.17 L b) 5.16 L c) 4.30 L d) 6.19 L 

21. Second exam
14- The volume of a sample of nitrogen is 7.20 liters at 35°C and atm. What volume will it occupy at STP?
a) 8.17 L b) 5.16 L c) 4.30 L d) 6.19 L 
V1=7.2 L, T1= 35C = =308K, P1= 0.970atm, P2= 1atm, T1=273 K, V2=?

22. a) from n = 1 to n = 4 b) from n = 1 to n = 2
Second exam
12- Which of the following electron transitions would absorb the lowest energy by the hydrogen atom?
a) from n = 1 to n = b) from n = 1 to n = 2
c) from n = 1 to n = d) from n = 1 to n = 6
13- Calculate the wavelength associated with a beam of neutrons moving at 7.0 x 102 m/s? (The mass of a neutron is x kg).
a) nm b) nm c) nm d) nm
14- The volume of a sample of nitrogen is 7.20 liters at 35°C and atm. What volume will it occupy at STP?
a) 8.17 L b) 5.16 L c) 4.30 L d) 6.19 L 

23. a) n = 2, l = 2, ml = –2, –1, 0, 1, 2 b) n = 2, l = 1, ml = 0
Second exam
15- Give the values of the quantum numbers (n, l and ml) associated with the 2p subshell?
a) n = 2, l = 2, ml = –2, –1, 0, 1, b) n = 2, l = 1, ml = 0
c) n = 2, l = 1, ml = d) n = 2, l = 1, ml = –1, 0, 1
16- The electron configuration of a neutral atom is 1s2 2s2 2p6 3s2. Name the element?
a) Si b) Na c)Mg d) Al
1s2 2s2 2p6 3s2 = =12=Mg

24. a) n = 2, l = 2, ml = –2, –1, 0, 1, 2 b) n = 2, l = 1, ml = 0
Second exam
15- Give the values of the quantum numbers (n, l and ml) associated with the 2p subshell?
a) n = 2, l = 2, ml = –2, –1, 0, 1, b) n = 2, l = 1, ml = 0
c) n = 2, l = 1, ml = d) n = 2, l = 1, ml = –1, 0, 1
16- The electron configuration of a neutral atom is 1s2 2s2 2p6 3s2. Name the element?
a) Si b) Na c)Mg d) Al
17- A ground-state atom of zinc (Zn) has ___ unpaired electrons and is _____.
a) 0, paramagnetic b) 1, paramagnetic
c) 2, paramagnetic d) 0, diamagnetic

25. a) 0, paramagnetic b) 1, paramagnetic
Second exam
17- A ground-state atom of zinc (Zn) has ___ unpaired electrons and is _____.
a) 0, paramagnetic b) 1, paramagnetic
c) 2, paramagnetic d) 0, diamagnetic
Zn=30e
[Ar] 4s2 3d10
4s d10

26. a) n = 2, l = 2, ml = –2, –1, 0, 1, 2 b) n = 2, l = 1, ml = 0
Second exam
15- Give the values of the quantum numbers (n, l and ml) associated with the 2p subshell?
a) n = 2, l = 2, ml = –2, –1, 0, 1, b) n = 2, l = 1, ml = 0
c) n = 2, l = 1, ml = d) n = 2, l = 1, ml = –1, 0, 1
16- The electron configuration of a neutral atom is 1s2 2s2 2p6 3s2. Name the element?
a) Si b) Na c)Mg d) Al
17- A ground-state atom of zinc (Zn) has ___ unpaired electrons and is _____.
a) 0, paramagnetic b) 1, paramagnetic
c) 2, paramagnetic d) 0, diamagnetic

27. a) Noble gases b) Halogens c) Alkali metals d) Alkaline earth metals
Second exam
18- The elements having ns1 configuration in their outermost shell are:
a) Noble gases b) Halogens
c) Alkali metals d) Alkaline earth metals
19- O-2 is isoelectronic with :
a) F– b) K c) Cl d) Ar
O-2 = 10e
F- = 10, Cl- =18, K +=20, Ar=18

28. a) Noble gases b) Halogens c) Alkali metals d) Alkaline earth metals
Second exam
18- The elements having ns1 configuration in their outermost shell are:
a) Noble gases b) Halogens
c) Alkali metals d) Alkaline earth metals
19- O-2 is isoelectronic with :
a) F– b) K c) Cl d) Ar
20- Electron affinity is highest for :
a) Cl b) I c) S d) Br

29. 20- Electron affinity is highest for : a) Cl b) I c) S d) Br
Second exam
20- Electron affinity is highest for :
a) Cl b) I c) S d) Br

30. a) Noble gases b) Halogens c) Alkali metals d) Alkaline earth metals
Second exam
18- The elements having ns1 configuration in their outermost shell are:
a) Noble gases b) Halogens
c) Alkali metals d) Alkaline earth metals
19- O-2 is isoelectronic with :
a) F– b) K c) Cl d) Ar
20- Electron affinity is highest for :
a) Cl b) I c) S d) Br
21- The electron configuration of V is:
a) [Ar]4s24p b) [Kr]4s23d c) [Ar] 4s23d d) [Kr]4s24p3

31. 22- Which of the following will form an ionic bond?
Second exam
22- Which of the following will form an ionic bond?
a) Mg and F b) Si and O c) C and O d) Cl and O
23- Pick out the correct statement from the following:
a) Alkali metals have the lowest ionization energy
b) Alkali metals have the highest ionization energy
c) Halogens have the lowest ionization energy
d) Inert gases have the lowest ionization energy
24- According to Lewis's theory, a covalent bond is formed by the:
a) Transfer of electrons b) Sharing of electrons
c) partial transfer of electrons d) Donation of electrons

32. 25- How many total valance electrons are available in CO2 ?
Second exam
25- How many total valance electrons are available in CO2 ?
a) b) c) d) 24
To answer this question and the following 3 questions we have to draw lewis structure
Step 1 – C is less electronegative than O, put C in center
Step 2 – Count valence electrons C - 4 (3s23p2) and O - 6 (2s22p4)
4+ (2 x 6) = 16 valence electrons
Step 3 – Draw single bonds between C and O atoms and complete
octets on C and O atoms.
Step 4 - Check, are # of e- in structure equal to number of valence e- ?
2 single bonds (2x2) + 8 lone pairs (8x2) = 20 valence electrons
Step 5 - Too many electrons, form double bond and re-check # of e- O C

33. 25- How many total valance electrons are available in CO2 ?
Second exam
25- How many total valance electrons are available in CO2 ?
a) b) c) d) 24
26- How many lone pairs of electrons are in CO2?
a) b) c) d) 0
27- How many resonance structures are there in CO2?
a) b) c) d) 0 O C O C O C

34. 25- How many total valance electrons are available in CO2 ?
Second exam
25- How many total valance electrons are available in CO2 ?
a) b) c) d) 24
26- How many lone pairs of electrons are in CO2?
a) b) c) d) 0
27- How many resonance structures are there in CO2?
a) b) c) d) 0
28- The formal charge on the carbon atom in CO2?
a) b) c) d) +2

35. ( ) - 28- The formal charge on the carbon atom in CO2?
Second exam
28- The formal charge on the carbon atom in CO2?
a) b) c) d) +2 O C 4 - -
(8)
= 0
formal charge on an atom in a Lewis structure = 1 2
total number of bonding electrons ( )
total number of valence electrons in the free atom -
total number of nonbonding electrons

36. 25- How many total valance electrons are available in CO2 ?
Second exam
25- How many total valance electrons are available in CO2 ?
a) b) c) d) 24
26- How many lone pairs of electrons are in CO2?
a) b) c) d) 0
27- How many resonance structures are there in CO2?
a) b) c) d) 0
28- The formal charge on the carbon atom in CO2?
a) b) c) d) +2

37. Total number of orbital = n2 = 32 = 9
Second exam
29- What is the total number of sub-orbital associated with the principal quantum number n = 3?
a) b) c) d) 2
Total number of orbital = n2 = 32 = 9

38. 30- Order the following according to increasing atomic radius.
Second exam
29- What is the total number of sub-orbital associated with the principal quantum number n = 3?
a) b) c) d) 2
30- Order the following according to increasing atomic radius.
N Be Mg C O B
a) N > O > Mg > Be > C > B b) O < N < C < B < Be < Mg
c) Mg< Be < B < C < N < O d) Be > Mg > B > C > N > O

39. 30- Order the following according to increasing atomic radius.
Second exam
30- Order the following according to increasing atomic radius.
N Be Mg C O B
a) N > O > Mg > Be > C > B b) O < N < C < B < Be < Mg
c) Mg< Be < B < C < N < O d) Be > Mg > B > C > N > O

40. 30- Order the following according to increasing atomic radius.
Second exam
29- What is the total number of sub-orbital associated with the principal quantum number n = 3?
a) b) c) d) 2
30- Order the following according to increasing atomic radius.
N Be Mg C O B
a) N > O > Mg > Be > C > B b) O < N < C < B < Be < Mg
c) Mg< Be < B < C < N < O d) Be > Mg > B > C > N > O

41. Thank you for listening