HCl is not used to make the medium acidic in oxidation reaction of ${\mathrm{KMnO}}_4$ , because

1.	Both HCl and  KMnO4 act as oxidising agents.
2.	KMnO4 oxidises HCl into Cl2, which is also an oxidising agent.
3.	KMnO4  is a weaker oxidising agent than HCl.
4.	KMnO 4 acts as a reducing agent in the presence of HCl.

Which of the following compounds cannot act as an oxidising agent?

Match the properties given in Column I with the metals given in Column II:

The oxidation state that cerium (Ce) most commonly exhibits are:

1. +2, +3
2. +2, +4
3. +3, +4
4. +3, +5

The correct order of decreasing second ionization enthalpy of Ti(22), V(23), Cr (24) and Mn(25) is :

1.  Cr > Mn > V > Ti

2.  V > Mn > Cr > Ti

3.  Mn > Cr > Ti > V

4.  Ti > V > Cr > Mn

Electronic configuration of a transition element X in +3 oxidation state is [Ar] 3d⁵. What is its atomic number?

1. 25

2. 26

3. 27

4. 24

Which of the following statements is true? 

Based on the metallic radii provided, which transition element exhibits the highest density?

1. Fe 

2. Ti

3. Co

4. Cu

A compound that has coloure in solid state is:

1. \(Ag_2SO_4\)

2. \(CuF_2\)

3. \(ZnF_2\)

4. \(Cu_2Cl_2\)

On addition of small amount of KMnO₄, to concentrated H₂SO₄, a green oily compound is obtained which is highly explosive in nature. What is the compound ?
$1. {\mathrm{Mn}}_2{\mathrm{O}}_7$
$2. {\mathrm{MnO}}_2$
$3. {\mathrm{MnSO}}_4$
$4. {\mathrm{Mn}}_2{\mathrm{O}}_3$