s-Block Elements
Ion having highest hydration enthalpy among the given alkaline earth metal ions is :
Structures of $\mathrm{BeCl}_{2}$ in solid state, vapour phase and at very high temperature respectively are :
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Gypsum is used for making fireproof wall boards.
Reason (R) : Gypsum is unstable at high temperatures.
In the light of the above statements, choose the correct answer from the options given below :
Match List I with List II :
| List I | List II | ||
|---|---|---|---|
| A. | Slaked lime | I. | $\mathrm{NaOH}$ |
| B. | Dead burnt plaster | II. | $\mathrm{Ca(OH)_2}$ |
| C. | Caustic soda | III. | $\mathrm{Na_2CO_3\cdot 10H_2O}$ |
| D. | Washing soda | IV. | $\mathrm{CaSO_4}$ |
Choose the correct answer from the options given below :
Choose the correct statement(s) :
A. Beryllium oxide is purely acidic in nature.
B. Beryllium carbonate is kept in the atmosphere of $\mathrm{CO_2}$.
C. Beryllium sulphate is readily soluble in water.
D. Beryllium shows anomalous behaviour.
Choose the correct answer from the options given below :
Lithium aluminium hydride can be prepared from the reaction of :
The alkaline earth metal sulphate(s) which are readily soluble in water is/are :
A. $\mathrm{BeSO}_{4}$
B. $\mathrm{MgSO}_{4}$
C. $\mathrm{CaSO}_{4}$
D. $\mathrm{SrSO}_{4}$
E. $\mathrm{BaSO}_{4}$
Choose the correct answer from the options given below :
The correct order of hydration enthalpies is
(A) K$^+$
(B) Rb$^+$
(C) Mg$^{2+}$
(D) Cs$^+$
(E) Ca$^{2+}$
Choose the correct answer from the options given below :
Which one among the following metals is the weakest reducing agent?
Which of the following represents the correct order of metallic character of the given elements?
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : The alkali metals and their salts impart characteristic colour to reducing flame.
Reason R : Alkali metals can be detected using flame tests.
In the light of the above statements, choose the most appropriate answer from the options given below :
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Beryllium has less negative value of reduction potential compared to the other alkaline earth metals.
Reason R : Beryllium has large hydration energy due to small size of Be$^{2+}$ but relatively large value of atomization enthalpy
In the light of the above statements, choose the most appropriate answer from the options given below :
Identify the correct statements about alkali metals.
A. The order of standard reduction potential (M$^+$ | M) for alkali metal ions is Na > Rb > Li.
B. CsI is highly soluble in water.
C. Lithium carbonate is highly stable to heat.
D. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
E. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below :
Match List I with List II
| List-I |
List-II |
||
|---|---|---|---|
| A. | Chlorophyll | I. | $\mathrm{Na_2CO_3}$ |
| B. | Soda ash | II. | $\mathrm{CaSO_4}$ |
| C. | Dentistry, Ornamental work | III. | $\mathrm{Mg^{2+}}$ |
| D. | Used in white washing | IV. | $\mathrm{Ca(OH)_2}$ |
Choose the correct answer from the options given below :
Reaction of BeO with ammonia and hydrogen fluoride gives A which on thermal decomposition gives $\mathrm{BeF_2}$ and $\mathrm{NH_4F}$. What is 'A'?
$\mathrm{Mg}\left(\mathrm{NO}_{3}\right)_{2} \cdot \mathrm{XH}_{2} \mathrm{O}$ and $\mathrm{Ba}\left(\mathrm{NO}_{3}\right)_{2} \cdot \mathrm{YH}_{2} \mathrm{O}$, represent formula of the crystalline forms of nitrate salts. Sum of $\mathrm{X}$ and $\mathrm{Y}$ is _____________.
Explanation:
Magnesium nitrate typically crystallizes as a hexahydrate, which means it has six water molecules in its crystal structure. So, X = 6.
On the other hand, barium nitrate commonly crystallizes as an anhydrous salt, meaning it does not incorporate water molecules into its crystal structure. So, Y = 0.
Therefore, the sum of X and Y would indeed be 6 + 0 = 6.
Explanation:
Li does not form superoxide.
K, Rb and Cs form stable super oxides but Cs has ionisation enthalpy less than 400 kJ. While K and Rb have ionisation enthalpy greater than 400 kJ mol–1.
On heating, $\mathrm{LiNO_3}$ gives how many compounds among the following __________
$\mathrm{Li_2O,N_2,O_2,LiNO_2,NO_2}$
Explanation:
$\mathrm{LiNO_3\buildrel \Delta \over \longrightarrow Li_2O+NO_2+O_2}$
Identify the incorrect reaction from the following.
$2 \mathrm{NaNO}_3 \longrightarrow 2 \mathrm{NaNO}_2+\mathrm{O}_2$
$2 \mathrm{LiNO}_3 \longrightarrow 2 \mathrm{LiNO}_2+\mathrm{O}_2$
$2 \mathrm{~Pb}\left(\mathrm{NO}_3\right)_2 \longrightarrow 2 \mathrm{PbO}+4 \mathrm{NO}_2+\mathrm{O}_2$
$\mathrm{Mg}_2 \mathrm{C}_3+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{CH}_3 \mathrm{C} \equiv \mathrm{CH}+\mathrm{Mg}(\mathrm{OH})_2$
The alkali metal with lowest $E^{\circ}{ }_{M^{+} / M}(\mathrm{~V})$ is $X$ and the alkali metal with highest $E^{\circ}{ }_{M^{+} / M}(\mathrm{~V})$ is $Y$. Then $X$ and $Y$ are respectively
$\mathrm{Li}, \mathrm{Na}$
$\mathrm{Li}, \mathrm{Cs}$
$\mathrm{Na}, \mathrm{Li}$
$\mathrm{Cs}, \mathrm{Li}$
Assertion (A) Be and Mg do not impart any colour to the flame.
Reason (R) The electrons in them are strongly bound to get excited by flame.
(A) and (R) are true (R) is the correct explanation of (A).
(A) and (R) are true, but (R) is not the correct explanation of (A).
(A) is correct but (R) is incorrect.
(A) is incorrect but (R) is correct.
Which one of the following statements is not correct?
Molecular formula of calgon is $\mathrm{NaAlSiO}_4$.
Beryllium halides are soluble in organic solvents.
Among alkali metals, the reducing property of sodium is least in aqueous solution.
White metal is an alloy of lithium.
Thermal decomposition of lithium nitrate gives
$\mathrm{LiO}_2, \mathrm{O}_2, \mathrm{NO}_2$
$\mathrm{Li}_2 \mathrm{O}, \mathrm{O}_2, \mathrm{~N}_2 \mathrm{O}$
$\mathrm{Li}_2 \mathrm{O}, \mathrm{O}_2, \mathrm{~N}_2$
$\mathrm{Li}_2 \mathrm{O}, \mathrm{O}_2, \mathrm{NO}_2$
Assertion (A) Alkali metals and their salts impart characteristic flame colours.
Reason (R) Alkali metals have low ionisation enthalpy values. So, electron excitation is possible. The correct option among the following is
(A) and (R) are true, (R) is the correct explanation of (A).
(A) and (R) are true, but (R) is not the correct explanation of (A).
(A) is true but (R) is false.
(A) is false but (R) is true.
Which of the following set of metals have strong tendency to form super oxides?
Identify the correct statements with respect to compounds of beryllium.
I. Beryllium oxide is amphoteric in nature.
II. Beryllium hydride is formed by the reaction of beryllium with hydrogen.
III. Beryllium hydride is formed by the reaction of beryllium chloride with lithium aluminium hydride.
IV. Beryllium sulpahte is the least soluble sulphate among the sulphates of alkaline earth metals.
Which one of the following decreasing orders of stability is correct?
Portland cement contains 'X' to enhance the setting time. What is 'X'?
Lithium nitrate and sodium nitrate, when heated separately, respectively, give :
The correct decreasing order for metallic character is :
Statement I : An alloy of lithium and magnesium is used to make aircraft plates.
Statement II : The magnesium ions are important for cell-membrane integrity.
In the light the above statements, choose the correct answer from the options given below :
Which of the following statement is incorrect?
An element A of group 1 shows similarity to an element B belonging to group 2. If A has maximum hydration enthalpy in group 1 then B is :
The metal that has very low melting point and its periodic position is closer to a metalloid is :
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: $\mathrm{LiF}$ is sparingly soluble in water.
Reason R: The ionic radius of $\mathrm{Li}^{+}$ ion is smallest among its group members, hence has least hydration enthalpy.
In the light of the above statements, choose the most appropriate answer from the options given below.
Reaction of $\mathrm{BeCl}_{2}$ with $\mathrm{LiAlH}_{4}$ gives :
(A) $\mathrm{AlCl}_{3}$
(B) $\mathrm{BeH}_{2}$
(C) $\mathrm{LiH}$
(D) $\mathrm{LiCl}$
(E) $\mathrm{BeAlH}_{4}$
Choose the correct answer from options given below :
The correct order of density is :
Choose the correct order of density of the alkali metals :
Match List - I with List - II :
| List-I | List-II | ||
|---|---|---|---|
| (a) | Sodium hydride | (i) | Lewis acid |
| (b) | Silane | (ii) | Saline hydride |
| (c) | Vanadium hydride | (iii) | Molecular hydride |
| (d) | Aluminium hydride | (iv) | Non-stoichiometric hydride |
Correct answer is :
Correct statement about alkali metal oxides is :
Amongst baking soda, caustic soda and washing soda, carbonate anion is present in :
Arrange the following in the decreasing order of their covalent character :
(A) LiCl
(B) NaCl
(C) KCl
(D) CsCl
Choose the most appropriate answer from the options given below :
Match List-I with List-II
| List-I (Metal) |
List-II (Emitted light wavelength (nm)) |
||
|---|---|---|---|
| (A) | Li | (I) | 670.8 |
| (B) | Na | (II) | 589.2 |
| (C) | Rb | (III) | 780.0 |
| (D) | Cs | (IV) | 455.5 |
Choose the most appropriate answer from the options given below :
Addition of H2SO4 to BaO2 produces :
BeCl2 reacts with LiAlH4 to give :
s-block element which cannot be qualitatively confirmed by the flame test is :
The correct order of melting point is :