Physical Properties (Group 1)

Q. What is the relation between hydration enthalpy and solubility?

Q. Transition metal compounds are usually coloured. This is due to the electronic transition :

1. from p-orbital to s-orbital.
2. from d-orbital to s-orbitals
3. from p-orbital to p-orbital.
4. d-d transition

Q.

Explain why is sodium less reactive than potassium?

Q. Why cu2+ has high hydration energy than cu+??

Q. The metallic lustre of sodium is explained by the presence of:

1. Inert gas configuration
2. $N{a}^{+}$ ions
3. BCC lattice
4. The oscillation of loosely bound electrons

Q.

Why is atomic density of K less than Na

Q. Which of the following complexes does not follow $EAN$ rule?

1. $\left[Fe\right(CN{)}_6{]}^{4-}$
2. $\left[Fe\right(CN{)}_6{]}^{3-}$
3. $Ni(CO{)}_4$
4. $\left[V\right(CO{)}_6{]}^{─}$

Q. Why potassium is lighter than sodium?

Q. Why does the thermal conductivity increases down the group in alkali metals?

Q.

Ionic mobility of which of the following alkali metal ions is lowest when aqueous solution of their salts are put under an electric field?

1. K
2. Rb
3. Li
4. Na

Q. Which of the following sequence correctly represents the decreasing acidic nature of oxides?

1. $Li{O}_2>BeO>B_2{O}_3<C{O}_2>N_2{O}_3$
2. $N_2{O}_3>C{O}_2>B_2{O}_3>BeO>L{i}_{2}O$
3. $C{O}_2>N_2{O}_3>B_2{O}_3>BeO>L{i}_{2}O$
4. $B_2{O}_3>C{O}_2>N_2{O}_3>L{i}_{2}O>BeO$

Q. Boron forms BF₄^- ion while aluminium forms AlF_{6^{3- ion, though they are in same group.why?}}

Q. Crude common salt becomes damp when kept open in air because:

1. None
2. $NaCl$ is hygroscopic in nature
3. It contains $MgC{l}_2$ and $CaC{l}_2$ as impurities which are deliquescent in nature
4. (a) and (b) both

Q. number of moles of ferrous sulphate oxidised by 1 mole of potassium permanganate in acidic medium is

Q. Why does the high hydration enthalpy account for high reducing power?

Q.

Halides of alkali metals are high melting solids.Explain

Q. Which of pair of ions will act as strong oxidising agents?

1. $M{n}^{3+}$ and $C{o}^{3+}$
2. $M{n}^{3+}$ and $S{c}^{3+}$
3. $C{o}^{3+}$ and $S{c}^{3+}$
4. $C{r}^{3+}$ and $T{i}^{3+}$

Q. Dear Sir,
On moving along the period in the transition series the density increases due to increases in mass and decrease in volume but what happens when we move down the group ? Plz explain sir

Q. If in the fermentation of sugar in an enzymatic solution which is intially 0.12M the concentration of sugar is reduced to 0.06M in 10h and to 0.03M in 20h , hence order of the reaction is
(a) 0
(b)1
(c) 2
(d) 3

Q. Considering greater polarization in $LiCl$ compared to that of $NaCl$, which of the following statements you would expect to be wrong ?

1. LiCl has more covalent character than NaCl
2. $LiCl$ has lower melting point than that of $NaCl$
3. $LiCl$ dissolves more in organic solvents
4. $LiCl$ will ionize in water more than $NaCl$

Q. Metals are generally electropositive then why do they accept a pair of electron donated by the lignads in complexes?Positive ligands being deficit of electrons donate a pair of electrons to metal ion during complex formation why?

Q. Element $Hg$ has two oxidation states $H{g}^{1+}$ & $H{g}^{2+}$, the correct order of radii of these ions?

1. $H{g}^{+1}<H{g}^{2+}$
2. $H{g}^{1+}>H{g}^{2+}$
3. $H{g}^{1+}=H{g}^{2+}$
4. $H{g}^{1+}\le H{g}^{2+}$

Q. What will be the ratio of molar volume to atomic volume for 1mol. of hydrogen ? (Take the size of molecule to be 1Angstrom) ?

Q. Solubility product of magnesium Hydroxide is 4 10-12 . The number of moles of magnesium ions in one litre of its saturated solution in 0.1M NaOH solution is 1)4 10-10 2)110-4 3)210-6 4)810-6

Q. ZnO turns yellow on heating. Why?

Q. Which of the following statements is correct :

1. Hydration energy of alkali metal ions increases down the group
2. Caesium and Potassium are used in photoelectric cell.
3. $Li$ does not form nitride on burning in air
4. except $L{i}_{2}C{O}_3$ all the carbonates of alkali metals decompose on heating

Q. the ksp of AgCrO4 is 1.1 ×10^-12 at 298K. the solubility of Ag2CrO4 in a 0.1 M AgNO3 solution is?

Q. Which of the following regarding alkali metals is not correct?

1. They tarnish in air
2. They are kept under kerosene
3. All alkali metals form oxides on burning in air
4. Reaction of water with alkali metal becomes more violent on going down the group

Q. 0.701g of silver salt of a dibasic acid on ignition yielded 0.497g of metallic silver . Molecular weight of the acid is

Q.

1)Lithium is the strongest reducing agent among all the akali metal inspite of high ionisation energy Give reason

2)Lithium forms only monoxide