Two well$-$known complex ions containing $Ni$ are $[Ni(H_{2}O{)}_6{]}^{2+},$ which is green, and $[Ni(en{)}_3{]}^{2+},$ which is purple. Which one of these

statements is true? A$)$ The crystal field splitting energy $($D$)$ is greater for $[Ni(en{)}_3{]}^{2+}$ than for $[Ni(H_{2}O{)}_6{]}^{2+}.$ B$)[Ni(en{)}_3{]}^{2+}$ absorbs energy in

the red region of the spectrum. C$)$Both complex ions are diamagnetic. D$)[Ni(H_{2}O{)}_6{]}^{2+}$ transmits light with wavelengths of approximately

$650-700nm.$

Consider the $[CoC{l}_6{]}^{4-}$ ion. Determine which responses are true statements. I. The oxidation number of Co is $-4.$ II$.$ The coordination number

of cobalt is $6.$

III. It is paramagnetic. IV$.$ It is a low$-$spin complex.

A$)$ I, II$,$ III, IV

B$)$ I, IV

C$)$ II$,$ III

D$)$ I, III

The normal freezing point of ammonia is $-78C.$ Predict the signs of $H,S,$ and $G$ for ammonia when it freezes at $-80C$ and $1$ atm: $NH{H}_3(l)$

$N{H}_3(s).$

A$.-{?}^H-{?}^S\frac{G}{0}$

B$.-+-$

C$.++$

D$.++0$

E$.--$

A$.$ A

B$.$ B

C$.$ C

D$.$ E

The normal boiling point of acetic acid is $118\mathrm{.}1C.$ If a sample of the acetic acid is at $125\mathrm{.}2C,$ predict the signs of $H,S,$ and $G$ for the

boiling process at this temperature. A$)H>0,S>0,G<mn\; id="EditorElement\_2374462">0</mn><mi\; id="EditorElement\_2374464">B</mi>$