208 + Interview Questions in THE-ALKALI-METALS IN GENERAL AWARENESS Page 4 InterviewSolution

151.	When CO is passed over solid NaOH heated to `200^(@)C` , it formsA. `Na_(2)CO_(3)`B. `H_(2)CO_(3)`C. `HCOONa`D. All.
Answer» Correct Answer - C `NaOH + CO rarr underset("Sod. formate")(HCOONa)`

Discussion

152.	Which one of the following acts as a reducing as well as oxidising agent ?A. `Na_(2)O`B. `Na_(2)O_(2)`C. `NaNO_(3)`D. `KNO_(3)`
Answer» Correct Answer - B `Na_(2)O_(2)` can act as oxidising agent as well as reducing agent.

Discussion

153.	When NaOH pallets are left in the open air they acquire a fluid layer around each crystal asA. they start meltingB. they absorb moisture from airC. they react with air to form a liquid compoundD. they absorb `CO_(2)` from air.
Answer» Correct Answer - B They absorb moisture from air because it is hygroscopic in nature.

Discussion

154.	The metal extracted by electrolysis of its fused salt isA. IronB. SodiumC. CopperD. Lead.
Answer» Correct Answer - B Sodium is extracted by the electrolysis of fused salt (NaCl).

Discussion

155.	The salt added to table salt to make it flow freely in rainly reason isA. KClB. `NH_(4)Cl`C. `Ca_(3)(PO_(4))_(2)`D. `NaHCO_(3)`.
Answer» Correct Answer - C Both calcium and phosphate are good for health and also prevent absorption of moisture.

Discussion

156.	A solution of sodium metal is liquid ammonia is strongly reducing due to the presence ofA. Sodium atomsB. Sodium hydrideC. Sodium amideD. Solvated electrons.
Answer» Correct Answer - D A solution of sodium metal in ammonia contains solvated electrons.

Discussion

157.	A solution of sodium metal in liquid ammonia is strongly reducing due to the presence ofA. Sodium atomsB. Sodium hydrideC. Sodium amideD. Solvated electrons.
Answer» Correct Answer - D A solution of sodium metal in liquid ammonia is highly reducing due to the presence of solvated electrons.

Discussion

158.	The alkali metal having low melting point isA. FrB. CsC. RbD. Na.
Answer» Correct Answer - A

Discussion

159.	Which of the following sodium halides has the highest melting point ?A. NaFB. NaClC. NaBrD. NaI.
Answer» Correct Answer - A The melting point depends on strength of ionic bond.

Discussion

160.	Which one is the highest melting halide ?A. NaClB. NaBrC. NaFD. NaI.
Answer» Correct Answer - C Melting points of alkali metal halides decreases in the order `NaF gt NaCl gt NaBr gt NaI`

Discussion

161.	Which halide has highest melting point ?A. NaClB. NaBrC. NaFD. NaI.
Answer» Correct Answer - C Melting points of alkali metal halides are in the order :

Discussion

162.	The correct order of reducing character of alkali metals isA. `Rb lt K lt Na lt Li`B. `Li lt Na lt K lt Rb`C. `Na lt K lt Rb lt Li`D. `Rb lt Na lt K lt Li`.
Answer» Correct Answer - C Li has the most negative `E^(@)` value while `E^(@)` values of other alkali metal become more and more negative as we, move down the group from Na to Rb. Option C is correct.

Discussion

163.	The alklali halide which is soluble in pyridine isA. NaClB. LiClC. KClD. CsCl
Answer» Correct Answer - B LiCl being covalent is soluble in organic solvents such as pyridine.

Discussion

164.	Li and Na metals are prepared electrolytically becauseA. Their salts are good conductors of electricity in liquid stateB. Their salt solutions conduct electricity easilyC. These metals themselves being stronger reducing agents, cannot be reduced by other reductantsD. Their salts can be fused easily.
Answer» Correct Answer - C Refer to comprehensive review.

Discussion

165.	Potassium metal is commerically prepared by the reduction of molten KCl with metallic sodium at `850^(@)C` (1123 K). This method is based upon the following principleA. Sodium is more reactive than potassium at this temperatureB. Potassium being more volatile distils off thus shifting the reaction forward.C. Sodium prefers to bind to chloride ions in preference to potassium ionsD. Potassium and sodium form an alloy at this temperature.
Answer» Correct Answer - B `KCl(l)+Na(l)overset(1123 K (850 ^(@)C))rarrNaCl(l) + K(g)` `{:(B.pt."of Na = "883^(@)C(1156 K)),(B.pt. "of K = "759^(@)C(1032 K)),(M.pt. "of NaCl = "600^(@)C(973 K)),(B. pt. "of KCl = "750^(@)C(1023 K)):}}"Under normal pressure"` AT the reaction temperature only potassium is in the vapour state and as such escape out of the reaction mixture.

Discussion

166.	Which of the following ion forms a hydroxide highly soluble in water ?A. `Ni^(2+)`B. `K^(+)`C. `Zn^(2+)`D. `Al^(3+)`.
Answer» Correct Answer - B Alkali metal hydroxides are easily soluble in water.

Discussion

167.	The sodium metal is prepared byA. Electrolysis of aqueous solution of NaClB. Electrolysis of aqueous solution of NaoHC. Electrolysis of molten NaClD. none of these.
Answer» Correct Answer - C

Discussion

168.	Alkali metals are generally extracted byA. Reduction methodsB. Double decomposition methodsC. Displacement methodsD. Electricity methods.
Answer» Correct Answer - D Alkali metals are generally extracted by electrolytic methods.

Discussion

169.	Alkali metals are generally prepared byA. reduction of metal oxides with carbonB. electrolysis of their anhydrous molten halidesC. reduction of halides with hydrogenD. reduction of corresponding oxide with powdered aluminium.
Answer» Correct Answer - B

Discussion

170.	The reaction of sodium is highly exothermic with water. The rate of reaction is lowered byA. mixing with alcoholB. mixing with acetic acidC. making an amalgamD. lowering the temperature.
Answer» Correct Answer - C In amalgam lesser surface area of alkali metal is available for reaction.

Discussion

171.	Which of the following statements concerning alkali metals is true ?A. They are powerful oxidation agentsB. They are powerful reducing agentsC. They have no oxidising or reducing propertyD. They are both oxidising and reducing agents.
Answer» Correct Answer - B Due to low I.E. these can loose valence electrons with ease and hence act as good reducing agents.

Discussion

172.	Pick the odd one outA. `1s^(1)`B. `1s^(2)2s^(1)`C. `1s^(2)2s^(2)2p^(6)3s^(1)`D. None.
Answer» Correct Answer - A `H(1s^(1))` is not an alkali metal.

Discussion

173.	Pick the odd one cutA. `1s^(2)2s^(1)`B. `1s^(2)2s^(2)2p^(6)3s^(1)`C. `1s^(2)2s^(2)2p^(6)3s^(2)3s^(6)3d^(10)4s^(1)`D. None.
Answer» Correct Answer - C Configuration C i.e., `1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(10)4s^(1)` is that of Cu, which is not an alkali metal.

Discussion

174.	Pick the odd one outA. `Li_(3)PO_(4)` is the most insoluble salt of LiB. LiI is the least stable alkali metal halideC. Solubility of `Li_(2)SO_(4)` decreases with increase in temperatureD. Li is the weakest reducing agent among alkali metals.
Answer» Correct Answer - D Li is the strongest reducing agent among alkali metals.

Discussion

175.	Highly pure dilute solution of sodium in liquid ammoniaA. Shows blue colourB. exhibits electrical conductivityC. produces sodium amideD. produces hydrogen gas.
Answer» Correct Answer - A::B A solution of highly pure sodium in liquid ammonia is quite stable and no chemical reaction takes place.

Discussion

176.	A highly concentrated solution (about 5 M) of an alkali metal in ammonia (pick the odd one out)A. is called expanded metalB. is highly unstableC. is diamagnetic in natureD. is bronze like in colour.
Answer» Correct Answer - B A highly concentrated solution of alkali metals (about 5M) in ammonia is meta-stable. It is called expanded metal. It is diamagnetic in nature. It is bronze like appearance.

Discussion

177.	The colour of the solution of alkali metal in ammonia can beA. blueB. violetC. bronze likeD. red.
Answer» Correct Answer - A::C Solution of alkalli metal in ammonia can be blue coloured (if not very concentrated) or bronzelike (if concentrated).

Discussion

178.	Alkali metals dissolve in ammonia to give a blue solution which is conducting due toA. ammoniated electronsB. loss of electronsC. ammoniated cationsD. both (A) and (C ).
Answer» Correct Answer - D Ammoniated electrons.

Discussion

179.	Alkali metal iodide(s) aqueous solution(s) of which can dissolve `I_(2)` to form `MI_(3)` is (are)A. KB. NaC. RbD. Cs.
Answer» Correct Answer - A::C Sodium cannot form polyhalide of the form `MI_(3)`

Discussion

180.	The alkali metals form salt like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orderA. NaH `gt` LiH `gt` KH `gt` RbH `gt` CsHB. LiH `gt` NaH `gt` KH `gt` RbH `gt` CsHC. CsH `gt` RbH `gt` KH `gt` NaH `gt` LiHD. KH `gt` NaH `gt` LiH `gt` CsH `gt` RbH.
Answer» Correct Answer - B As the size of the alkali metal ion increases, lattice energy decreases and hence, the stability of the corresponding metal hydride decreases.

Discussion

181.	Which of the following statements is correct for `CsBr_(3)` ?A. It is a covalent compoundB. It contains `Cs^(3+)` and `Br^(-)` ionsC. It contains `Cs^(+)` and `Br_(3)^(-)` ionsD. It contains `Cs^(+)`, `Br^(-)` and `Br_(2)` molecule.
Answer» Correct Answer - C `CsBr_(3)` contains `Cs^(+)` and `Br_(3)^(-)` ions.

Discussion

182.	If NaOH is added to an aqueous solution of `Zn^(+2)` ions white precipitate appears and on adding excess NaOH, the precipitate dissolves. In solution zinc is in theA. Cationic partB. Anionic partC. Both in cationic and anionic partsD. There is no zinc left in the solution.
Answer» Correct Answer - B `Zn^(2+)+2NaOHrarr2Na^(2+)+Zn(OH)_(2)` `Zn(OH)_(2)+2NaOHrarrNa_(2)ZnO_(2)+2H_(2)O` `Na_(2)ZnO_(2)` ionises as 2 `Na^(+)` and `[ZnO_(2)]^(2-)` `therefore` Zinc occurs as anion.

Discussion

183.	Which is an ore of potassium ?A. CarnalliteB. CryoliteC. BauxiteD. Dolomite
Answer» Correct Answer - A Carnallite, KCl.MgCl_(2).6H_(2)O` is an ore of potassium.

Discussion

184.	Oxone isA. CaOB. `N_(2)O`C. `Na_(2)O_(2)`D. `NaBO_(3)`.
Answer» Correct Answer - C Oxone is `Na_(2)O_(2)`.

Discussion

185.	Compared with the alkaline earth metals, the alkali metals exhibitA. Smaller ionic radiiB. Highest boiling pointsC. Greater hardnessD. Lower ionization energies.
Answer» Correct Answer - D Alkali metals have lower ionisation energy (first) than alkaline earth metals.

Discussion

186.	Baking powder has one of the following constituentsA. `Na_(3)CO_(3)`B. `Na_(2)SO_(4)`C. `NaHCO_(3)`D. `K_(2)CO_(3)`.
Answer» Correct Answer - C Baking powder contains `NaHCO_(3)`, starch and an acidic component.

Discussion

187.	The ion which has the maximum value of hydration energy isA. `Li^(+)`B. `Na^(+)`C. `K^(+)`D. `Cs^(+)`
Answer» Correct Answer - A Smaller the size, greater is the hydration energy.

Discussion

188.	Which of the following alkali metal hydroxides is the strongest base ?A. LiOHB. NaOHC. KOHD. CsOH.
Answer» Correct Answer - D Base strength of alkali metal hydroxides increases down the group as the size of `M^(+)` increases. As such CsOH is the strongest base.

Discussion

189.	The alkali metal which acts as a nutrient for plants isA. NaB. KC. LiD. Rb.
Answer» Correct Answer - B Potassium acts as a nutrient for plants.

Discussion

190.	Washing soda has formulaA. `Na_(2)CO_(3).7H_(2)O`B. `Na_(2)CO_(3).10H_(2)O`C. `Na_(2)CO_(3).3H_(2)O`D. `Na_(2)CO_(3)`.
Answer» Correct Answer - B Washing soda is `Na_(2)CO_(3).10H_(2)O`

Discussion

191.	Strongest bond is betweenA. CsFB. NaClC. Both (A) and (B)D. None of these.
Answer» Correct Answer - A Cs is most electropositive and F is most electronegative. Therefore, strongest ionic bond is in CsF.

Discussion

192.	Make the incorrect statement about lithiumA. Lithium metal is not affected by airB. When burnt in oxygen, lithium metal form superoxide, `LiO_(2)`C. Lithium combines with nitrogen directly to form lithium nitrideD. Lithium has great tendency to form hydrates.
Answer» Correct Answer - B Actually lithium form oxdies.

Discussion

193.	Point out the incorrect statement about lithium in the followingA. It is softer than other alkali metalsB. It possesses higher melting and boiling pointsC. It is least reactiveD. It forms chloride which is soluble in alcohol.
Answer» Correct Answer - A Lithium is harder than other alkali metals.

Discussion

194.	The properties of lithium are similar to those of Mg. This is becauseA. Both have nearly the same sizeB. the ratio of their charge to size is nearly the sameC. Both have similar electronic configurationsD. Both are found together in nature.
Answer» Correct Answer - A Li(152 pm) and Mg (160 pm) have nearly same size.

Discussion

195.	Which one is not a mineral of sodium ?A. Rock saltB. Chile saltpetreC. CyroliteD. Petalite.
Answer» Correct Answer - D Petalite is a mineral of lithium.

Discussion

196.	Which of the following compounds will be formed, when Lithium is heated with excess of oxygen ?A. `Li_(2)O_(2)`B. `LiO_(2)`C. `Li_(2)O`D. LiO.
Answer» Correct Answer - C `4Li+O_(2)rarr2Li_(2)O`

Discussion

197.	Sodium reacts with water more vigorously than lithium becauseA. It has higher atomic weightB. It is more electronegativeC. It is more electropositiveD. It is a metal.
Answer» Correct Answer - C Sodium is more electropositive than lithium.

Discussion

198.	Sodium metal reacts with `Al_(2)O_(3)` at high temperature to give a sodium compound X X reacts with carbon dioxide in water to form Y.Y isA. `Na_(2)O_(2)`B. `Na_(2)O`C. `Na_(2)CO_(3)`D. `NaAlO_(2)`
Answer» Correct Answer - C `6Na+Al_(2)O_(3) rarrunderset((X))(3Na_(2)O)+2Al` `Na_(2)O+CO_(2)rarrunderset((Y))(Na_(2)CO_(3))`

Discussion

199.	The reaction `Na_(2)S+I_(2)+Na_(2)SO_(3)rarrNa_(2)S_(2)O_(3)+2NaI` is calledA. Springs ReactionB. Friedal craft reactionC. Blanc reductionD. Solvay reaction.
Answer» Correct Answer - A Springs reaction.

Discussion

200.	`Na_(2)CO_(3)+Fe_(2)O_(3)rarr A+CO_(2)`, what is A in the reaction ?A. `Na_(3)FeO_(3)`B. `Fe_(3)O_(4)`C. `Na_(2)FeO_(2)`D. `NaFeO_(2)`.
Answer» Correct Answer - D `Na_(2)CO_(3)+Fe_(2)O_(3)rarr2NaFeO_(2)+CO_(2)`

Discussion

Explore topic-wise InterviewSolutions in .

When CO is passed over solid NaOH heated to `200^(@)C` , it formsA. `Na_(2)CO_(3)`B. `H_(2)CO_(3)`C. `HCOONa`D. All.

Which one of the following acts as a reducing as well as oxidising agent ?A. `Na_(2)O`B. `Na_(2)O_(2)`C. `NaNO_(3)`D. `KNO_(3)`

When NaOH pallets are left in the open air they acquire a fluid layer around each crystal asA. they start meltingB. they absorb moisture from airC. they react with air to form a liquid compoundD. they absorb `CO_(2)` from air.

The metal extracted by electrolysis of its fused salt isA. IronB. SodiumC. CopperD. Lead.

The salt added to table salt to make it flow freely in rainly reason isA. KClB. `NH_(4)Cl`C. `Ca_(3)(PO_(4))_(2)`D. `NaHCO_(3)`.

A solution of sodium metal is liquid ammonia is strongly reducing due to the presence ofA. Sodium atomsB. Sodium hydrideC. Sodium amideD. Solvated electrons.

A solution of sodium metal in liquid ammonia is strongly reducing due to the presence ofA. Sodium atomsB. Sodium hydrideC. Sodium amideD. Solvated electrons.

The alkali metal having low melting point isA. FrB. CsC. RbD. Na.

Which of the following sodium halides has the highest melting point ?A. NaFB. NaClC. NaBrD. NaI.

Which one is the highest melting halide ?A. NaClB. NaBrC. NaFD. NaI.

Which halide has highest melting point ?A. NaClB. NaBrC. NaFD. NaI.

The correct order of reducing character of alkali metals isA. `Rb lt K lt Na lt Li`B. `Li lt Na lt K lt Rb`C. `Na lt K lt Rb lt Li`D. `Rb lt Na lt K lt Li`.

The alklali halide which is soluble in pyridine isA. NaClB. LiClC. KClD. CsCl

Which of the following ion forms a hydroxide highly soluble in water ?A. `Ni^(2+)`B. `K^(+)`C. `Zn^(2+)`D. `Al^(3+)`.

The sodium metal is prepared byA. Electrolysis of aqueous solution of NaClB. Electrolysis of aqueous solution of NaoHC. Electrolysis of molten NaClD. none of these.

Alkali metals are generally extracted byA. Reduction methodsB. Double decomposition methodsC. Displacement methodsD. Electricity methods.

Alkali metals are generally prepared byA. reduction of metal oxides with carbonB. electrolysis of their anhydrous molten halidesC. reduction of halides with hydrogenD. reduction of corresponding oxide with powdered aluminium.

The reaction of sodium is highly exothermic with water. The rate of reaction is lowered byA. mixing with alcoholB. mixing with acetic acidC. making an amalgamD. lowering the temperature.

Which of the following statements concerning alkali metals is true ?A. They are powerful oxidation agentsB. They are powerful reducing agentsC. They have no oxidising or reducing propertyD. They are both oxidising and reducing agents.

Pick the odd one outA. `1s^(1)`B. `1s^(2)2s^(1)`C. `1s^(2)2s^(2)2p^(6)3s^(1)`D. None.

Pick the odd one cutA. `1s^(2)2s^(1)`B. `1s^(2)2s^(2)2p^(6)3s^(1)`C. `1s^(2)2s^(2)2p^(6)3s^(2)3s^(6)3d^(10)4s^(1)`D. None.

Pick the odd one outA. `Li_(3)PO_(4)` is the most insoluble salt of LiB. LiI is the least stable alkali metal halideC. Solubility of `Li_(2)SO_(4)` decreases with increase in temperatureD. Li is the weakest reducing agent among alkali metals.

Highly pure dilute solution of sodium in liquid ammoniaA. Shows blue colourB. exhibits electrical conductivityC. produces sodium amideD. produces hydrogen gas.

A highly concentrated solution (about 5 M) of an alkali metal in ammonia (pick the odd one out)A. is called expanded metalB. is highly unstableC. is diamagnetic in natureD. is bronze like in colour.

The colour of the solution of alkali metal in ammonia can beA. blueB. violetC. bronze likeD. red.

Alkali metals dissolve in ammonia to give a blue solution which is conducting due toA. ammoniated electronsB. loss of electronsC. ammoniated cationsD. both (A) and (C ).

Alkali metal iodide(s) aqueous solution(s) of which can dissolve `I_(2)` to form `MI_(3)` is (are)A. KB. NaC. RbD. Cs.

Which of the following statements is correct for `CsBr_(3)` ?A. It is a covalent compoundB. It contains `Cs^(3+)` and `Br^(-)` ionsC. It contains `Cs^(+)` and `Br_(3)^(-)` ionsD. It contains `Cs^(+)`, `Br^(-)` and `Br_(2)` molecule.

If NaOH is added to an aqueous solution of `Zn^(+2)` ions white precipitate appears and on adding excess NaOH, the precipitate dissolves. In solution zinc is in theA. Cationic partB. Anionic partC. Both in cationic and anionic partsD. There is no zinc left in the solution.

Which is an ore of potassium ?A. CarnalliteB. CryoliteC. BauxiteD. Dolomite

Oxone isA. CaOB. `N_(2)O`C. `Na_(2)O_(2)`D. `NaBO_(3)`.

Compared with the alkaline earth metals, the alkali metals exhibitA. Smaller ionic radiiB. Highest boiling pointsC. Greater hardnessD. Lower ionization energies.

Baking powder has one of the following constituentsA. `Na_(3)CO_(3)`B. `Na_(2)SO_(4)`C. `NaHCO_(3)`D. `K_(2)CO_(3)`.

The ion which has the maximum value of hydration energy isA. `Li^(+)`B. `Na^(+)`C. `K^(+)`D. `Cs^(+)`

Which of the following alkali metal hydroxides is the strongest base ?A. LiOHB. NaOHC. KOHD. CsOH.

The alkali metal which acts as a nutrient for plants isA. NaB. KC. LiD. Rb.

Washing soda has formulaA. `Na_(2)CO_(3).7H_(2)O`B. `Na_(2)CO_(3).10H_(2)O`C. `Na_(2)CO_(3).3H_(2)O`D. `Na_(2)CO_(3)`.

Strongest bond is betweenA. CsFB. NaClC. Both (A) and (B)D. None of these.

Make the incorrect statement about lithiumA. Lithium metal is not affected by airB. When burnt in oxygen, lithium metal form superoxide, `LiO_(2)`C. Lithium combines with nitrogen directly to form lithium nitrideD. Lithium has great tendency to form hydrates.

Point out the incorrect statement about lithium in the followingA. It is softer than other alkali metalsB. It possesses higher melting and boiling pointsC. It is least reactiveD. It forms chloride which is soluble in alcohol.

The properties of lithium are similar to those of Mg. This is becauseA. Both have nearly the same sizeB. the ratio of their charge to size is nearly the sameC. Both have similar electronic configurationsD. Both are found together in nature.

Which one is not a mineral of sodium ?A. Rock saltB. Chile saltpetreC. CyroliteD. Petalite.

Which of the following compounds will be formed, when Lithium is heated with excess of oxygen ?A. `Li_(2)O_(2)`B. `LiO_(2)`C. `Li_(2)O`D. LiO.

Sodium reacts with water more vigorously than lithium becauseA. It has higher atomic weightB. It is more electronegativeC. It is more electropositiveD. It is a metal.

Sodium metal reacts with `Al_(2)O_(3)` at high temperature to give a sodium compound X X reacts with carbon dioxide in water to form Y.Y isA. `Na_(2)O_(2)`B. `Na_(2)O`C. `Na_(2)CO_(3)`D. `NaAlO_(2)`

The reaction `Na_(2)S+I_(2)+Na_(2)SO_(3)rarrNa_(2)S_(2)O_(3)+2NaI` is calledA. Springs ReactionB. Friedal craft reactionC. Blanc reductionD. Solvay reaction.

`Na_(2)CO_(3)+Fe_(2)O_(3)rarr A+CO_(2)`, what is A in the reaction ?A. `Na_(3)FeO_(3)`B. `Fe_(3)O_(4)`C. `Na_(2)FeO_(2)`D. `NaFeO_(2)`.