Head Elements (Group 1)

Q. What is the formula to calculate the radius of an orbit of the atom and velocity of the specific shell of the atom.

Q.

Why does lattice enthalpy decrease down the group?

Q. Which allotrope of phosphorus is the most reactive?

1. White phosphorus
2. $\alpha$-Black phosphorus
3. Red phosphorus
4. $\beta$-Black phosphorus

Q.

Sublimation energy is the heat required to change one mole of solid to gas.

I don't understand why metals have sublimation energy, the reason being that they are solid substances and even at very high temperatures, they exist as a liquid. How can there be a metal in gaseous form?

Q. The correct order of relative stability of half-filled and completely filled subshells is?

1. 

2. 

3. 

4. 

Q. Which of the following metals does not forms solid hydrogen carbonates?

1. Na and K
2. Li and Mg
3. Li and Na
4. Li and K

Q.

The metal used in solar cells is

1. Cesium

2. Tin

3. Gold

4. Sodium

Q.

Why Li as a solid has high electical and thermal conductivity?

Q.

What are the valencies of cuprous and cupric ions?

1. +1 and +2

2. +2 and +3

3. +3 and +4

4. +1 and +3

Q. Among the s block elements, Lithium is the only metal to form a nitride directly. True or false?

1. True

2. False

Q. Explain Ionisation enthalpy decreases in a group from top to bottom?

Q. A metal crystallizes in cubic close packed ccp. The atomic radius of metal is 144 pm and its atomic mass is 197 a.m.u its density is

Q.

Which is the largest atom in Group 14?

Q.

The element with the maximum density in the group $14$ is _____.

Q.

Give Reason: Metal forms positive ions.

Q.

Why does ${\mathrm{KMnO}}_4$ shows the d-d transition?

Q. Match the atomic number 19, 15, 8, 4, and 2 with each of the following:

(i) A metal of valency one.

Q. Which of the following has highest ionic radii?

1. $C{r}^{3+}$
2. $M{n}^{3+}$
3. $F{e}^{3+}$
4. $C{o}^{3+}$

Q.

The metals of group 2 from top to bottom are Be, Mg, Ca, Sr and Ba which of these metals will form ions more readily and why?

Q. The first member of each group from 13 to 17 of the p–block elements differ in many respects from the other members of their respective groups because of:

1. Small size
   
2. High Electronegativity
   
3. Absence of d–orbitals
   
4. All of the above.

Q.

Carnation is diamagnetic or paramagnetic

Q. Which of the following anion has the lowest hydration enthalpy?

1. $F^{-}$
2. $C{l}^{-}$
3. $B{r}^{-}$
4. $I^{-}$

Q. Arrange Li, Na, K, Rb, Cs in order of increasing ionization energy:

1. None of these
2. $Cs<Rb<K<Na<Li$
3. $K<Rb<Cs<Na<Li$
4. $Cs<K<Rb<Na<Li$

Q.

Give one chemical test to distinguish between the following pairs of compounds.
Zinc sulphate solution and Zinc chloride solution.

Q. Metallic lustre exhibited by Na is explained by the presence of

1. ions
2. Conduction of electrons
3. free photons
4. BCC lattice

Q. Increasing order of atomic radii
Li, Na, K, Rb, Cs :

1. Li < Na < K < Rb < Cs
2. Li < Na < K < Cs < Rb
3. Li < K < Na< Rb < Cs
4. None of these

Q. The increasing order of the density of alkali metals :

1. Li < K < Na < Rb < Cs
2. Li < Na < K < Rb < Cs
3. Cs < Rb < Na < K < Li
4. Li < Na < Rb < K < Cs
5. Cs < Rb < K < Na < Li

Q. According to the Cahn-Ingold-Prelog system, the atoms with the highest ___ get the highest priority.

1. Atomic number
2. Atomic weight
3. Altitude
4. Atomic mass

Q. Arrange Li, Na, K, Rb, Cs in order of increasing electronegativity:

1. $Cs<Rb=Na<Li<K$
2. $Cs<Rb=K<Na<Li$
3. $Rb<Cs=Li<Na<L$
4. None of these

Q. Which of the following alkali metal ions has lowest ionic mobility in aqueous solution?

1. $R{b}^{+}$
2. $C{a}^{+}$
3. $N{a}^{+}$
4. $L{i}^{+}$