Chemistry Home Work: 11/07/14

Give the number of unpaired electrons present in a ground-state atom of Fe.

Answer: 4

Give the number of unpaired electrons present in a ground-state atom of S.

Answer: 2

Give the number of unpaired electrons present in a ground-state atom of Tl.

Answer: 1

Give the number of unpaired electrons present in a ground-state atom of Cr.

Answer: 6

Give the number of unpaired electrons present in a ground-state atom of Fe²⁺.

Answer: 4

Give the number of unpaired electrons present in a ground-state of the ion formed when one electron is ionized from an O atom.

Answer: 3

Give the number of unpaired electrons present in a ground-state atom of Se^2-.

Answer: 0

Give the number of unpaired electrons present in a ground-state atom of Al³⁺.

Answer: 0

Using the abbreviated notation, the ground-state electron configuration of Y³⁺ is

Answer: [Kr] -- Is the correct answer.

Y losses three electron to become Y+ and attains the electronic configuration of Kr.

Using the abbreviated notation, the ground-state electron configuration of Br^- is

Answer: [Kr] -- Br gains an electron to become Br-. Therefore, it has same electronic configuration as Kr

Using the abbreviated notation, the ground-state electron configuration of Rh²⁺ is

Answer: [Kr] 4d^{7 -- The electronic configuration of Rh is [Kr] 5s2 4d7. it looses 2 electron from outer orbital that is 5s. why? because n = 5 is outer orbital comes before 4d}

Using only a periodic table as a guide, arrange each of the following series of atoms in order of increasing size.

Answer: a. Be, Li, Na Correct

b. Be, Na, Li

c. Na, Be, Li

d. Na, Li, Be

e. Li, Na, Be

f. Li, Be, Na

Using only a periodic table as a guide, arrange each of the following series of atoms in order of increasing size.

Answer: a. F, N, P Correct

b. F, P, N

c. P, F, N

d. P, N, F

e. N, P, F

f. N, F, P

Note: Please refer to the above Image for getting correct answer

Using only a periodic table as a guide, arrange each of the following series of atoms in order of increasing size.

Answer: a. O, I, Sn Correct

b. O, Sn, I

c. Sn, I, O

d. Sn, O, I

e. I, Sn, O

f. I, O, Sn

Note: Please refer to the above Image for getting correct answer

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing size.

Answer: a. O^2-, F, F^-

b. O^2-, F^-, F

c. F^-, F, O^2-

d. F^-, O^2-, F

e. F, O^2-, F^-

f. F, F^-, O^2- Correct

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing size.

Answer: a. Al³⁺, Mg, Na Correct

b. Al³⁺, Na, Mg

c. Na, Al³⁺, Mg

d. Na, Mg, Al³⁺

e. Mg, Na, Al³⁺

f. Mg, Al³⁺, Na

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing size.

Answer: a. N, P, Si Correct

b. N, Si, P

c. Si, N, P

d. Si, P, N

e. P, Si, N

f. P, N, Si

Indicate which species in each pair has the higher ionization energy.

Answer: Select one or more:

a. Between K and I, I Correct

b. Between K and I, K

c. Between Al and Al⁺, Al

d. Between Al and Al⁺, Al⁺ Correct

e. Between Ar and Cl^-, Ar Correct

f. Between Ar and Cl^-, Cl^-

g. Between Mg and Ca, Mg Correct

h. Between Mg and Ca, Ca

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing first ionization energy.

Answer: a. K, Se, S Correct

b. K, S, Se

c. S, K, Se

d. S, Se, K

e. Se, K, S

f. Se, S, K

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing first ionization energy.

Answer: a. Cr, As, O Correct

b. Cr, O, As

c. O, Cr, As

d. O, As, Cr

e. As, Cr, O

f. As, O, Cr

Using only a periodic table as a guide, arrange each of the following series of species in order of increasing first ionization energy.

Answer: a. O, O^-, F

b. O, F, O^-

c. F, O, O^-

d. F, O^-, O

e. O^-, F, O

f. O^-, O, F Correct

Which electron configuration represents the most highly excited state of C?

Answer: a. 1s²2s²2px¹2py¹

b. 1s²2s²2px²

c. 1s²2s¹2px¹2py¹2pz¹

d. 1s¹2s²2px¹2py¹2pz¹ Correct

The Word is Most Excited Stated . In most excited state the inner electron jumps out

the S orbital and moves to P orbital to make it half-filled P orbital.

Write the electron configuration of the copper atom and the 2⁺ cation of copper. Check the correct choices.

Answer: a. Cu [Ar] 4s²3d⁹

b. Cu [Ar] 4s¹3d¹⁰ Correct

c. Cu [Ar] 4s⁰3d¹¹

d. Cu²⁺ [Ar] 4s²3d⁹

e. Cu²⁺ [Ar] 4s⁰3d⁹ Correct

f. Cu²⁺ [Ar] 4s²3d⁷

Which ground-state electron configuration represents the element with the largest size?

Answer: a. 1s²2s²2p¹ Correct

b. 1s²2s²2p⁴

c. 1s²2s²2p⁵

d. 1s²2s²2p³

Note: Refer to Atomic Radius Trend

Which ground-state electron configuration represents the element with the smallest ionization energy?

Answer: a. 1s²2s²2p¹ Correct

b. 1s²2s²2p⁴

c. 1s²2s²2p⁵

d. 1s²2s²2p³

Which ground-state electron configuration represents the element with the most negative electron affinity?

Answer: a. 1s²2s²2p¹

b. 1s²2s²2p⁴

c. 1s²2s²2p⁵ Correct

d. 1s²2s²2p³

Arrange the elements lithium, carbon, and oxygen in order of increasing size.

Answer: a. O, C, Li Correct

b. O, Li, C

c. C, Li, O

d. C, O, Li

e. Li, C, O

f. Li, O, C

Arrange the elements lithium, carbon, and oxygen in order of increasing first ionization energy.

Answer: a. O, C, Li

b. O, Li, C

c. C, Li, O

d. C, O, Li

e. Li, C, O Correct

f. Li, O, C

Arrange the elements lithium, carbon, and oxygen in order of increasing second ionization energy.

Answer: a. O, C, Li

b. O, Li, C

c. C, Li, O

d. C, O, Li Correct

e. Li, C, O

f. Li, O, C

Arrange the elements lithium, carbon, and oxygen in order of increasing number of unpaired electrons. (There are two correct choices since 2 have the same number.)

Answer: a. O, C, Li

b. O, Li, C

c. C, Li, O

d. C, O, Li

e. Li, C, O Correct

f. Li, O, C Correct

In the reaction of lithium with oxygen, what expected compound is formed? If the compound is written Li_xO_y, what is x+y? For example, water is H₂O. In this case x =2, y = 1, and you write 3 in the space provided for the answer.

Answer: 3

Write the equation for the reaction, if any, of lithium with nitrogen. If there is a reaction forming Li_xN_y, what is x+y?

Answer: 4

Write the equation for the reaction, if any, of lithium with water. What products are formed?

Answer: a. No reaction

b. H₂ gas

c. O₂ gas

d. Li⁺(aq) Correct

e. OH^-(aq) Correct

f. H⁺(aq)

Write the electron configuration of the alkali metal (M) that reacts with oxygen to yield an oxide, M₂O, if 1.22 g of the metal reacts with 1.41 g of oxygen to form 2.63 g of the oxide.

Answer: a. [He] 2s¹ Correct

b. [Ne] 3s¹

c. [Ar] 4s¹

d. [Kr] 5s¹

e. [Xe] 6s¹

In the reaction of iron and chlorine, what mass of iron is needed to prepare 16.29 g of the iron chloride product if, under the conditions of the reaction, the electron configuration of the iron cation in the product is 1s²2s²2p⁶3s²3p⁶3d⁶?

Answer: 7.18g

How to : (16.29 g fecl2 ) * (1 mol fecl2 / 126.751g fecl2) = 0.1285 moles of fecl2

0.1285Moles of fecl2 * 55. 85 grams of fe = 7.18g

Which of the following reactions produce H₂ gas?

Answer: a. Na(s) + cold water Correct

b. NaH + cold water Correct

c. Na₂O + cold water

d. Mg + cold water

e. Ni + cold water

Which of the following reactions produce a basic solution (the hydroxide ion)?

Answer: a. Na(s) + cold water Correct

b. NaH + cold water Correct

c. Na₂O + cold water Correct

d. Mg + cold water

e. Ni + cold water

Which of the following reactions produces iron, the metal?

Answer: a. FeCl₃(aq) + Zn(s) Correct

b. FeCl₃(aq) + Cu(s)

c. FeCl₃(aq) + Ca(NO₃)₂(aq)

d. FeCl₃(aq) + Br₂(l)

e. FeCl₃(aq) + F₂(g)

Which of the following reactions produces chlorine gas?

Answer: a. FeCl₃(aq) + Zn(s)

b. FeCl₃(aq) + Cu(s)

c. FeCl₃(aq) + Ca(NO₃)₂(aq)

d. FeCl₃(aq) + Br₂(l)

e. FeCl₃(aq) + F₂(g) Correct

Match oxides with correct property.

Answer:

CaO	Answer 1
K₂O	Answer 2
CO₂	Answer 3
N₂O₅	Answer 4
Al₂O₃	Answer 5

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