MCQ
Identify the metal that forms colourless compounds.
- AIron (Z = 26)
- BChromium (Z = 24)
- CVanadium (Z = 23)
- DScandium (Z = 21)
✓
Answer
- Scandium (Z = 21)
Explanation:
Scandium(Z = 21) forms colourless compounds.
Scandium(Z = 21) has valence shell electron configuration of 3d14s2
In its +3 oxidation state, it looses 3 electrons and has valence shell electron configuration of 3d°4s°. Since no unpaired electron is present, it forms colourless compounds.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Which of the following ether can not be synthesised by Williamson's ether synthesis
Aniline reacts with mixed acid (conc. $HNO _3$ and conc. $H _2 SO _4$ ) at $288 K$ to give $P (51 \%)$,
→$Q (47 \%)$ and $R (2 \%)$. The major product(s) of the following reaction sequence is (are)
$\begin{array}{l}\begin{array}{ll}\text { 1) } Ac _2 O \text {, pyridine } \quad \text { 1) } Sn / HCl \end{array} \\ R \xrightarrow{2) Br _2, CH _3 CO _2 H } S \quad \xrightarrow{2) Br _2 / H _2 O \text { (excess) }} \text { major product(s) } \\ \text { 3) } H _3 O ^{+} \quad \text {3) } NaNO _2, HCl / 273-278 K \\ \text { 4) } NaNO _2, HCl / 273-278 K \quad \text { 4) } H _3 PO _2 \\ \text { 5) } EtOH , \Delta \\\end{array}$
Isopropyl bromide on Wurtz reaction gives:
The graph which represents the following reaction is :
→$\left( C _6 H _5\right)_3 C - Cl \frac{ OH ^{-}}{\text {Pyridine }}\left( C _6 H _5\right)_3 C - OH$
Stadard electromotive force for following cell is $ Zn|Zn^{+2}\, (1\,M)| |I^{\circleddash}\,(1\,M)| CuI| Cu$ if halfcell reaction ........... $\mathrm{V}$
→$CuI_{(s)} + e^{\circleddash} \to Cu_{(s)} + I^{\circleddash}_{(aq)}$ ; $E^o = -0.17\, V$
$Zn^{+2}_{(aq)} + 2e^{\circleddash} \to Zn_{(s)}$ ; $E^o = -0.76\, V$
For a zero - order reaction,
On the basis of position in the electrochemical series, the metal which does not displace hydrogen from water and acid is
Which one of the following is the true covalent oxide of iodine
Which biomolecule forms starch iodine complex
In the reaction, product $P$ is
→