1. Second exam

2. 1-Asample of nitrogen gas has a volume of 32.1 L at 20 °C. The gas is heated to 220 °C at constant pressure. The final volume of nitrogen is: a- 2.94 L b- 19.3 Lc- 45.0 Ld- 54.0 L V1= 32.1L, T1= 20 °C = 293 K, T2= 220 °C = 493K, V2= ?, n1=n2, P1=P2

3. Second exam 1-Asample of nitrogen gas has a volume of 32.1 L at 20 °C. The gas is heated to 220 °C at constant pressure. The final volume of nitrogen is: a- 2.94 L b- 19.3 Lc- 45.0 Ld- 54.0 L 2- The volume occupied by 32.75g of methane gas (CH 4 ) at 25 °C and 1.0 atm is : a- 0.186L b- 4.5 L c- 50.0L d- 80.0L m= 32.75g, T= 25 °C= 298 K, P= 1atm n = m/MM = 32.75 / 16 = 2.05 mol PV=nRT

4. Second exam 1-Asample of nitrogen gas has a volume of 32.1 L at 20 °C. The gas is heated to 220 °C at constant pressure. The final volume of nitrogen is: a- 2.94 L b- 19.3 Lc- 45.0 Ld- 54.0 L 2- The volume occupied by 32.75g of methane gas (CH 4 ) at 25 °C and 1.0 atm is : a- 0.186L b- 4.5 L c- 50.0L d- 80.0L 3- what is the molar mass of Freon-11 gas if its density is 6.12 g/L at STP? a- 0.274 g/mol b- 3.64 g/mole c- 78.2 g/mol d- 137 g/mol

5. Second exam 1-Asample of nitrogen gas has a volume of 32.1 L at 20 °C. The gas is heated to 220 °C at constant pressure. The final volume of nitrogen is: a- 2.94 L b- 19.3 Lc- 45.0 Ld- 54.0 L 2- The volume occupied by 32.75g of methane gas (CH 4 ) at 25 °C and 1.0 atm is : a- 0.186L b- 4.5 L c- 50.0L d- 80.0L 3- what is the molar mass of Freon-11 gas if its density is 6.12 g/L at STP? a- 0.274 g/mol b- 3.64 g/mole c- 78.2 g/mol d- 137 f/mol 4- A mixture of gases contain 0.31 mol CH 4, 0.05 mole He and 0.25 mol3 C 2 H 6 the total pressure is 1.5 atm. What is the partial pressure of He? a- 0.12 atm b- 0.76 atm c- 0.61 atm d- 123 atm

6. Second exam 4- A mixture of gases contain 0.31 mol CH 4, 0.05 mole He and 0.25 mol C 2 H 6 the total pressure is 1.5 atm. What is the partial pressure of He? a- 0.12 atm b- 0.76 atm c- 0.61 atm d- 123 atm n CH4 = 0.31 mol, n He = 0.05mol, n C2H6 =0.25mol, P T = 1.5atm

7. Second exam 1-Asample of nitrogen gas has a volume of 32.1 L at 20 °C. The gas is heated to 220 °C at constant pressure. The final volume of nitrogen is: a- 2.94 L b- 19.3 Lc- 45.0 Ld- 54.0 L 2- The volume occupied by 32.75g of methane gas (CH 4 ) at 25 °C and 1.0 atm is : a- 0.186L b- 4.5 L c- 50.0L d- 80.0L 3- what is the molar mass of Freon-11 gas if its density is 6.12 g/L at STP? a- 0.274 g/mol b- 3.64 g/mole c- 78.2 g/mol d- 137 f/mol 4- A mixture of gases contain 0.31 mol CH 4, 0.05 mole He and 0.25 mol3 C 2 H 6 the total pressure is 1.5 atm. What is the partial pressure of He? a- 0.12 atm b- 0.76 atm c- 0.61 atm d- 123 atm

8. Second exam 5- The volume (in ml) of 0.884 g of CO 2 at STP is: a- 0.45ml b- 450 ml c- 22.4 ml d- 45ml m = 0.884g, T=273 K, P= 1atm n= m/MM = 0.884 / 44 =0.02 mol PV=nRT

9. Second exam 5- The volume (in ml) of 0.884 g of CO 2 at STP is: a- 0.45ml b- 450 ml c- 22.4 ml d- 45ml 6- The pressure of a gas is measured at 912 torr. This pressure = a- 1.2 atm b- 12 atm c- 21.1 atm d- 21.2 atm 1 atm ==  760 torr ? atm ==  912 torr 912 /760 = 1.2 atm

10. Second exam 5- The volume (in ml) of 0.884 g of CO 2 at STP is: a- 0.45ml b- 450 ml c- 22.4 ml d- 45ml 6- The pressure of a gas is measured at 912 torr. This pressure = a- 1.2 atm b- 12 atm c- 21.1 atm d- 21.2 atm 7- calculate the frequency of visible light having a wavelength of 486 nm a- 2.06 x 10 14 s -1 b- 2.06 x 10 6 s -1 c- 6.17 x 10 14 s -1 d- 7.16 x 10 -14 s -1 λ = 486 nm = 486 x 10 -9 m c = λν v=c/λ = 3 x 10 8 / 486 x 10 -9 = 6.17 x 10 14 s -1

11. Second exam 5- The volume (in ml) of 0.884 g of CO 2 at STP is: a- 0.45ml b- 450 ml c- 22.4 ml d- 45ml 6- The pressure of a gas is measured at 912 torr. This pressure = a- 1.2 atm b- 12 atm c- 21.1 atm d- 21.2 atm 7- calculate the frequency of visible light having a wavelength of 486 nm a- 2.06 x 10 14 s -1 b- 2.06 x 10 6 s -1 c- 6.17 x 10 14 s -1 d- 7.16 x 10 -14 s -1 8- Complete this sentence: Atoms emit visible and ultraviolet light : a- as electrons transfer from lower energy levels to higher levels. b- as electrons transfer from higher energy levels to lower levels. c- as they heated and the solid melts to form liquid. d- as electrons move within an orbit.

12. Second exam 9- What is the energy in joules of one photon of microwave radiation with a wavelength 0.122 m? a- 2.70 x 10 -24 J b- 5.43 x 10 -24 J c- 1.63 x 10 -24 J d- 4.07 x 10 -24 J

13. Second exam 9- What is the energy in joules of one photon of microwave radiation with a wavelength 0.122 m? a- 2.70 x 10 -24 J b- 5.43 x 10 -24 J c- 1.63 x 10 -24 J d- 4.07 x 10 -24 J 10- “No two electrons in the same atom can have the same four quantum numbers” is a statement of: a- The Pauli exclusion principle. b- Bohr’s equation c- Hund’s rule d- de Broglie’s relation 11- The frequency of the light emitted by a hydrogen atom during a transition of its electron from n=4 to the n=1 is: a- 1.35 x 10 -15 s -1 b- 1.03 x 10 15 s -1 c- 8.03 x 10 15 s -1 d- 3.09 x 10 15 s -1

14. Second exam 11- The frequency of the light emitted by a hydrogen atom during a transition of its electron from n=4 to the n=1 is: a- 1.35 x 10 -15 s -1 b- 1.03 x 10 15 s -1 c- 8.03 x 10 15 s -1 d- 3.09 x 10 15 s -1

15. Second exam 9- What is the energy in joules of one photon of microwave radiation with a wavelength 0.122 m? a- 2.70 x 10 -24 J b- 5.43 x 10 -24 J c- 1.63 x 10 -24 J d- 4.07 x 10 -24 J 10- “No two electrons in the same atom can have the same four quantum numbers” is a statement of: a- The Pauli exclusion principle. b- Bohr’s equation c- Hund’s rule d- de Broglie’s relation 11- The frequency of the light emitted by a hydrogen atom during a transition of its electron from n=4 to the n=1 is: a- 1.35 x 10 -15 s -1 b- 1.03 x 10 15 s -1 c- 8.03 x 10 15 s -1 d- 3.09 x 10 15 s -1

16. Second exam 12- Which one of the following sets of quantum numbers is not possible? a- n=3, l=2, m l =-2, m s =+1/2 b- n=3, l=2, m l =-3, m s =+1/2 c- n=3, l=0, m l =0, m s =+1/2 d- n=3, l=1, m l =1, m s = +1/2 13- How many maximum electrons in an orbital labeled l=1? a- 5 b- 6 c- 10 d-14 L=1 =p

17. Second exam 12- Which one of the following sets of quantum numbers is not possible? a- n=3, l=2, m l =-2, m s =+1/2 b- n=3, l=2, m l =-3, m s =+1/2 c- n=3, l=0, m l =0, m s =+1/2 d- n=3, l=1, m l =1, m s = +1/2 13- How many maximum electrons in an orbital labeled l=1? a- 5 b- 6 c- 10 d-14 14- How many orbitals in an atom having the quantum numbers: n=3, l=2? a- 3 b- 5 c- 7 d- 14 2l +1 (2x2)+1 = 5

18. Second exam 12- Which one of the following sets of quantum numbers is not possible? a- n=3, l=2, m l =-2, m s =+1/2 b- n=3, l=2, m l =-3, m s =+1/2 c- n=3, l=0, m l =0, m s =+1/2 d- n=3, l=1, m l =1, m s = +1/2 13- How many maximum electrons in an orbital labeled l=1? a- 5 b- 6 c- 10 d-14 14- How many orbitals in an atom having the quantum numbers: n=3, l=2? a- 3 b- 5 c- 7 d- 14 15-How many unpaired electrons dose a ground-state atom of sulfur have? a- 0 b- 1 c- 2 d- 3 S=16e 1s 2 2s 2 2p 6 3s 2 3p 4 3s 2 3p 4

19. Second exam 12- Which one of the following sets of quantum numbers is not possible? a- n=3, l=2, m l =-2, m s =+1/2 b- n=3, l=2, m l =-3, m s =+1/2 c- n=3, l=0, m l =0, m s =+1/2 d- n=3, l=1, m l =1, m s = +1/2 13- How many maximum electrons in an orbital labeled l=1? a- 5 b- 6 c- 10 d-14 14- How many orbitals in an atom having the quantum numbers: n=3, l=2? a- 3 b- 5 c- 7 d- 14 15-How many unpaired electrons dose a ground-state atom of sulfur have? a- 0 b- 1 c- 2 d- 3

20. Second exam 16- The electron configuration of S -2 is : a- 1s 2 2s 2 2p 6 3s 2 3p 4 b- 1s 2 2s 2 2p 6 3s 2 3p 6 c- 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 2 d- 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 S -2 = 18 e 1s 2 2s 2 2p 6 3s 2 3p 6

21. Second exam 16- The electron configuration of S -2 is : a- 1s 2 2s 2 2p 6 3s 2 3p 4 b- 1s 2 2s 2 2p 6 3s 2 3p 6 c- 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 2 d- 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 17- The elements in group 2A are known by what name? a- Transition metals b- Halogen c- Alkali metals d- Alkali earth metals 18- Which one of these elements is a transition element? a- Nickel b- Tin c- Sodium d- Sulfur 19- The general electron configuration for atoms of all elements in group 5A is a- ns 2 nd 3 b- ns 2 np 5 c- ns 2 np 4 d- ns 2 np 3

22. Second exam 20- In what group of the periodic table is the element with the elecgron configuration : [Ar]4s 2 3d 10 4p 3 ? a- 2A b- 3A c- 5A d- 7A Ar=18 e 18+2+10+3 =33 e= As

23. Second exam 20- In what group of the periodic table is the element with the electron configuration : [Ar]4s 2 3d 10 4p 3 ? a- 2A b- 3A c- 5A d- 7A 21- In which of these pairs of atoms would the bond be the most polar? a- C-C b- C-N c- C-O d- C-S

24. Second exam 20- In what group of the periodic table is the element with the electron configuration : [Ar]4s 2 3d 10 4p 3 ? a- 2A b- 3A c- 5A d- 7A 21- In which of these pairs of atoms would the bond be the most polar? a- C-C b- C-N c- C-O d- C-S 22- Which ion is isoelectronic with Ar? a- Fe +2 b- F - c- Br - d- Ca +2 Ar = 18 e Fe +2 =24 e, F - = 10e, Br - = 36e, Ca +2 = 18e

25. Second exam 20- In what group of the periodic table is the element with the electron configuration : [Ar]4s 2 3d 10 4p 3 ? a- 2A b- 3A c- 5A d- 7A 21- In which of these pairs of atoms would the bond be the most polar? a- C-C b- C-N c- C-O d- C-S 22- Which ion is isoelectronic with Ar? a- Fe +2 b- F - c- Br - d- Ca +2 23- Which of these choices is the electron configuration of the iron (III) ion? a- [Ar] 3d 5 b-[Ar] 4s 1 3d 5 c- [Ar] 4s 2 3d 3 d- [Ar] 3d 6 Fe = 26e = [Ar] 4s 2 3d 6 Fe +3 = 23 e= [Ar] 3d 5

26. Second exam 20- In what group of the periodic table is the element with the electron configuration : [Ar]4s 2 3d 10 4p 3 ? a- 2A b- 3A c- 5A d- 7A 21- In which of these pairs of atoms would the bond be the most polar? a- C-C b- C-N c- C-O d- C-S 22- Which ion is isoelectronic with Ar? a- Fe +2 b- F - c- Br - d- Ca +2 23- Which of these choices is the electron configuration of the iron (III) ion? a- [Ar] 3d 5 b-[Ar] 4s 1 3d 5 c- [Ar] 4s 2 3d 3 d- [Ar] 3d 6

27. Second exam 24- Which one of these atoms has the largest atomic radius: K, P, S, Cl a- P b- K c- Cl d- S 25- Which of these compound is most likely to be covalent? a- Rb 2 S b- CuCl 2 c- CS 2 d- CaO 26- The de Broglie wavelength of a ball which has a mass of 250 g and traveling with a speed of 32.9 m/s is : a- 8.1 x10 33 m b- 8.1 x 10 -35 m c- 8.1 x 10 -33 m d- 8.1 x 10 35 m m =250 g = 0.25 kg, u= 32.9 m/s

28. Second exam 24- Which one of these atoms has the largest atomic radius: K, P, S, Cl a- P b- K c- Cl d- S 25- Which of these compound is most likely to be covalent? a- Rb 2 S b- CuCl 2 c- CS 2 d- CaO 26- The de Broglie wavelength of a ball which has a mass of 250 g and traveling with a speed of 32.9 m/s is : a- 8.1 x10 33 m b- 8.1 x 10 -35 m c- 8.1 x 10 -33 m d- 8.1 x 10 35 m 27- How many total valance electrons are available in PO 4 -3 ? a- 18 b- 32 c- 29 d- 30 P= 5, O=6, charge =+3 5+(4X6)+3 =32

29. Second exam 24- Which one of these atoms has the largest atomic radius: K, P, S, Cl a- P b- K c- Cl d- S 25- Which of these compound is most likely to be covalent? a- Rb 2 S b- CuCl 2 c- CS 2 d- CaO 26- The de Broglie wavelength of a ball which has a mass of 250 g and traveling with a speed of 32.9 m/s is : a- 8.1 x10 33 m b- 8.1 x 10 -35 m c- 8.1 x 10 -33 m d- 8.1 x 10 35 m 27- How many total valance electrons are available in PO 4 -3 ? a- 18 b- 32 c- 29 d- 30

30. Second exam 28- How many lone pairs of electrons are there in PO 4 -3 ? a- 12 b- 9 c- 6 d-24 Step 1 – P is less electronegative than O, put Cl in center Step 2 – Count valence electrons P - 5 (3s 2 3p 3 ) and O - 6 (2s 2 2p 4 ) 5+ (4 x 6)+3 = 32 valence electrons Step 3 – Draw single bonds between P and O atoms and complete octets on P and O atoms. Step 4 - Check, are # of e - in structure equal to number of valence e - ? 4 single bonds (4x2) + 12 lone pairs (12x2) = 32 valence electrons OPO O O

31. Second exam 28- How many lone pairs of electrons are there in PO 4 -3 ? a- 12 b- 9 c- 6 d-24 29- How many resonance structures are there in PO 4 -3 ? a- 0 b- 4 c- 2 d- 3 30- The formal charge on the phosphorus atom in PO 4 -3 ? a- 0 b- +2 c- (-1) d- +1

32. Second exam 30- The formal charge on the phosphorus atom in PO 4 -3 ? a- 0 b- +2 c- (-1) d- +1 OPO O O 5-0-½(8)= +1 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 -

33. Second exam 28- How many lone pairs of electrons are there in PO 4 -3 ? a- 12 b- 9 c- 6 d-24 29- How many resonance structures are there in PO 4 -3 ? a- 0 b- 4 c- 2 d- 3 30- The formal charge on the phosphorus atom in PO 4 -3 ? a- 0 b- +2 c- (-1) d- +1