Q: Calculate the energy released if 1.50 g of $$\mathrm{U}_{92}^{235}$$ undergoes fission according to the equation: $$\mathrm{U}_{92}^{235} + \mathrm{n}_{0}^{1} \rightarrow \mathrm{Ba}_{56}^{141} + \mathrm{Kr}_{36}^{92} + 3\mathrm{n}_{0}^{1}. $$Use $$\Delta E = \Delta m c^2$ and the following masses: $$\mathrm{U}_{92}^{235}$$ nucleus = 235.044 g/mol, neutron = 1.00869 g/mol, $$\mathrm{Ba}_{56}^{141}$$ nucleus = 140.914 g/mol, $$\mathrm{Kr}_{36}^{92}$$ nucleus = 91.926 g/mol.

$$(1.27 \pm 0.02) \times 10$$^{12}$$ J released

Question 1

Which of the following particles is emitted during alpha decay, and what is its correct nuclear notation?

Accepted Answer

$$\mathrm{He}_{2}^{4}$$

Question 2

Which isotope below is expected to be the least stable based on its atomic number and mass number?

Accepted Answer

$$\mathrm{Po}_{84}^{210}$$

Question 3

What is the electron configuration for $$\mathrm{Cr}^{+}$$?

Accepted Answer

[Ar] $$4s^1$$ $$3d^5$$

Question 4

Which nuclide would release energy via nuclear fission?

Accepted Answer

$$\mathrm{Th}_{90}^{232}$$

Question 5

Which ligand is expected to result in the largest crystal field splitting energy in a transition metal complex?

Accepted Answer

CN$$^{-}$$

Question 6

A single electron capture transforms $$\mathrm{K}_{19}^{40}$$ into which nuclide?

Accepted Answer

$$\mathrm{Ar}_{18}^{40}$$

Question 7

A solution of an unknown metal complex appears blue. Which color of light is it absorbing?

Accepted Answer

Red

Question 8

What is the coordination number for the complex ion $$[\mathrm{Co(en)}_3]^{2+}$$?

Accepted Answer

6

Question 9

What is the charge on iron in the complex ion $$[\mathrm{Fe(en)}_2(\mathrm{CN})_2]F$$?

Accepted Answer

+2

Question 10

Diethylenetriamine is a ligand with three nitrogen donor atoms. What type of coordination would you expect for this ligand?

Accepted Answer

tridentate

Question 11

Select the particle that properly completes the following nuclear reaction: $$\mathrm{Pu}_{94}^{244} \rightarrow \mathrm{U}_{92}^{240} + \ ?$$

Accepted Answer

$$\mathrm{He}_{2}^{4}$$

Question 12

Which of the following complex ions could possibly have an octahedral geometry?

Accepted Answer

$$[\mathrm{Cu(H_2O)_6}]^{+}$$

Question 13

What is the proper formula for potassium triaquatrichlororhodate(II)?

Accepted Answer

K$$_2$$[Rh(H$$_2O$$)$$_3Cl$_3$$]

Question 14

What is the correct formula for hexane?

Accepted Answer

C$$_6H$_{14}$$

Question 15

Which of the following would likely be a low spin complex?

Accepted Answer

[Fe(CO)$$_6$$]$$^{2+}$$

Question 16

A fossil sample has a radioactivity of $$3.97 	imes 10^6$ Bq. A fresh sample of the same mass has an activity of 1.58$$ 	imes $$10^7 Bq. If $$the half-life of $$^{14}C is 5370 $$years, how old is the fossil? Use $$t = \frac{1}{k} \ln \left(\frac{A_0$}{A}ight)$$ and $$k = \frac{\ln 2}{t_{1/2}}.$$

Accepted Answer

$$(10,700 \pm 200)$$ years

Question 17

Which of the following would be expected to be diamagnetic?

Accepted Answer

[Fe(CO)$$_6$$]$$^{2+}$$

Question 18

Calculate the energy released if 1.50 g of $$\mathrm{U}_{92}^{235}$$ undergoes fission according to the equation: $$\mathrm{U}_{92}^{235} + \mathrm{n}_{0}^{1} \rightarrow \mathrm{Ba}_{56}^{141} + \mathrm{Kr}_{36}^{92} + 3\mathrm{n}_{0}^{1}. $$Use $$\Delta E = \Delta m c^2$ and the following masses: $$\mathrm{U}_{92}^{235}$$ nucleus = 235.044 g/mol, neutron = 1.00869 g/mol, $$\mathrm{Ba}_{56}^{141}$$ nucleus = 140.914 g/mol, $$\mathrm{Kr}_{36}^{92}$$ nucleus = 91.926 g/mol.

Accepted Answer

$$(1.27 \pm 0.02) 	imes 10$$^{12}$$ J released

Question 19

Which of the following would be expected to absorb light in the green region (around 550 nm) based on the spectrochemical series and crystal field splitting?

Accepted Answer

[Fe(CN)$$_6$$]$$^{4-}$$

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