Aqua Regia

Q.

With reference to aqua regia, choose the correct option(s):

1. Aqua regia is prepared by mixing conc. $\mathrm{HCl}$ and conc. ${\mathrm{HNO}}_3$ in $3:1$ molar ratio.

2. Reaction of gold with aqua regia produces an anion having $\mathrm{Au}$ in $+3$ oxidation state.

3. Reaction of gold with aqua regia produces ${\mathrm{NO}}_2$ in the absence of air

4. The yellow color of aqua regia is due to the presence of $\mathrm{NOCl}$ & ${\mathrm{Cl}}_2$.

Q. Urea reacts with water to form $A$ which will decompose to form $B$. $B$ when passed through $C{o}^{3+}\text{(aq)}$, yellow coloured solution $C$ is formed. What is the formula of $C$ from the following?

1. ${\left[Co\right(N{H}_3{)}_6]}^{3+}$
2. $CoO$
3. $C{o}_2(S{O}_4{)}_3$
4. $C{o}_3{O}_4$

Q.

Name the gas produced

i. by the action of dilute nitric acid on copper, and

ii. on heating sodium nitrate.

Q. Gold dissolves in aqua regia to give:

1. $H\left[AuC{l}_4\right]$
2. $AuN{O}_3$
3. $H_2\left[AuC{l}_6\right]$
4. $Au(N{O}_3{)}_3$

Q. When mercury is heated with aqua regia then which compound is formed?

1. $Hg(N{O}_3{)}_2$
2. $HgC{l}_2$
3. $Hg(N{O}_2{)}_2$
4. $H{g}_{2}C{l}_2$

Q. Gold dissolves in aqua regia to give:

1. $Au(N{O}_3{)}_3$
2. $H\left[AuC{l}_4\right]$
3. $AuN{O}_3$
4. $H_2\left[AuC{l}_6\right]$

Q. With reference to aqua regia, choose the correct option(s)

1. The yellow colour of aqua regia is due to the presence of NOCl and $C{l}_2$
2. Aqua regia is prepared by mixing conc. HCl and conc. $HN{O}_3$ in 3 : 1 (v/v) ratio
3. Reaction of gold with aqua regia produces an anion having Au in +3 oxidation state
4. Reaction of gold with aqua regia produces $N{O}_2$ in the absence of air

Q. Concentrated nitric acid dissolves gold.
If true then enter 1, if false then enter 0.

Q. Aqua regia is used to dissolve noble metals such as Pt(Platinum) and Au(Gold).

1. False
2. True

Q. Aqua regia is a mixture of:

1. 3 parts of concentrated $HCl$ and 2 part of concentrated $HN{O}_3$
2. 2 parts of concentrated $HCl$ and 1 part of concentrated $HN{O}_3$
3. 3 parts of concentrated $HCl$ and 1 part of concentrated $HN{O}_3$
4. 3 parts of concentrated $H_{2}S{O}_4$ and 2 part of concentrated $HN{O}_3$

Q. Unreacted silver bromide in photographic plate is removed by the addition of hypo$\left(N{a}_2{S}_2{O}_3\right)$. If true enter 1, esle enter 0.

Q. A mixture of slaked lime, sand and water is known as :

1. lime mortar
2. concrete
3. RCC
4. clinker

Q. Aqua regia is a mixture of:

1. 3 parts of concentrated $HCl$ and 2 part of concentrated $HN{O}_3$
2. 2 parts of concentrated $HCl$ and 1 part of concentrated $HN{O}_3$
3. 3 parts of concentrated $HCl$ and 1 part of concentrated $HN{O}_3$
4. 3 parts of concentrated $H_{2}S{O}_4$ and 2 part of concentrated $HN{O}_3$

Q. Gun powder is mixture of powdered charcoal, potassium nitrate and ______ .

Q. When mercury is heated with aqua regia then which compound is formed?

1. $Hg(N{O}_3{)}_2$
2. $HgC{l}_2$
3. $Hg(N{O}_2{)}_2$
4. $H{g}_{2}C{l}_2$

Q. With reference to aqua regia, choose the correct option(s)

1. The yellow colour of aqua regia is due to the presence of NOCl and $C{l}_2$
2. Aqua regia is prepared by mixing conc. HCl and conc. $HN{O}_3$ in 3 : 1 (v/v) ratio
3. Reaction of gold with aqua regia produces an anion having Au in +3 oxidation state
4. Reaction of gold with aqua regia produces $N{O}_2$ in the absence of air

Q. Aqua regia is used to dissolve noble metals such as Pt(Platinum) and Au(Gold).

1. False
2. True