Highly soluble hydroxide in water is formed by -
1. Ni2+
2. K+
3. Zn2+
4. Al3+
A colourless salt gives violet colour to Bunsen flame and also turns moistured litmus paper blue. It Is:
1. Na2CO3
2. KNO3
3. K2CO3
4. Cu(OH)2
Hypo is chemically:
1. Na2S2O3.2H2O
2. Na2S2O3.3H2O
3. Na2S2O3.4H2O
4. Na2S2O3.5H2O
If NaOH is added to an aqueous solution of Zn2+ ions, a white precipitate appears and on adding axcess NaOH, the precepitate dissolves. In this solution zinc exists in the:
1. cationic part
2. anionic part
3. both in cationic and anionic parts
4. there is no zinc left in the solution
Brine is chemically:
1. conc. solution of Na2CO3
2. conc. solution of Na2SO4
3. conc. solution of NaCl
4. conc. solution of alum
Sodium reacts with water less vigorously than potassium because:
1. it has higher atomic weight
2. it is less electropositive
3. it is more electronegative
4. it is metal
NO2 is obtained by heating:
1. CsNO3
2. KNO3
3. LiNO3
4. NaNO3
Common table salt becomes moist and does not pour easily in rainy season because:
1. It contains magnesium chloride.
2. It contains magnesium carbonate.
3. It melts slightly in rainy season.
4. Sodium chloride is hygroscopic.
Excess of dilute sodium hydroxide solution is gradually added with shaking to an aqueous solution of zinc sulphate. What would you observe?
1. A light blue precipitate is first formed which finally dissolves to give a deep blue solution
2. A white precipitate appears which dissolves to give a colourless solution.
3. A white precipitation is formed which does not dissolve
4. No change takes place and the solution remains clear
The products of the electrolysis of aqueous solution of common salt are:
1. Na + Cl2
2. H2 + O2
3. NaOH + H2 + Cl2
4. NaOH + Cl2 + O2
KO2 is used in oxygen cylinder in space air craft and submarines because it:
1. absorbs CO2 and increase O2 content
2. eliminate moisture
3. absorbs CO2
4. produces O2
Potash alum is used in purification of water because:
1. it kills the micro-organisms
2. it precipitates the colloidal matter
3. it removes the hardness of water
4. it catalyses the removal of impurities
The byproduct of the Solvay process is:
1. CO2
2. NH3
3. CaCl2
4. CaCO3
The raw materials in Solvay process are:
1. NaOH, CaO and NH3
2. Na2CO3, CaCO3, and NH3
3. Na2SO4, CaCO3 and NH3
4. NaCl, NH3, CaCO3
Manufacture of NaOH is done by:
1. Castner - Kellner process
2. Solvay process
3. Brine process
4. Mond's process
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because:
1. it reacts with kerosene
2. it floats to the surface of kerosene because of low density
3. it does not react with air and H2O
4. none of the above
When CO2 is bubbled into an aqueous solution of Na2CO3, the following is formed:
1. H2O
2. OH-
3. NaHCO3
4. NaOH
The principal products obtained on heating iodine with concentrated caustic soda solution are:
1. NaOI + NaI
2. NaIO3 + Nal
3. NaOI + NaIO3 + NaI
4. NaIO4 + NaI
Which of the following acts as reducing agent as well as oxidising agent?
1. Na2O
2. Na2O2
3. NaNO3
4. KNO3
Which of the following alkali metal ion in aqueous solution is the best conductor of electricity?
(1) Li+
(2) Na+
(3) Cs+
(4) K+
A compound soluble in pyridine is:-
1. LiCl
2. CsCl
3. NaCl
4. KCl
Ionic mobility of which of the following alkali metal ions is lowest when an aqueous solution of their salts are put under an electric field?
(1) Na
(2) K
(3) Rb
(4) Li
The incorrect statement among the following regarding Beryllium is-
1. It is rendered passive by nitric acid.
2. lt forms Be2C
3. It's salts rarely hydrolyze.
4. It's hydride is electron-deficient and polymeric.
Which of the statements is not true?
1. On passing H2S through acidified K2Cr2O7 solution, a milky colour is observed
2. Na2Cr2O7 is preferred over K2Cr2O7 in volumteric analysis
3. K2Cr2O7 solution in acidic medium is orange
4. K2Cr2O7 solution becomes yellow on increasing the pH beyond 7
The solubility of metal halides depends on their nature, lattice enthalpy and hydration enthalpy of the individual ions. Amongst fluorides of alkali metals, the lowest solubility of LiF in water is due to:
(1) Ionic nature of lithium fluoride
(2) High lattice enthalpy
(3) High hydration enthalpy of lithium ion
(4) Low ionisation enthalpy of lithium atom
The effect of addion of gypsum to cement is-
1. It reduces the setting time of cement .
2. The setting time of cement increases.
3. The colour of cement becomes light .
4. A shining surface is obtained.
Calcium imide on hydrolysis gives gas (B) which on oxidation by bleaching powder gives gas (C). Gas (C) on reaction with magnesium give compound (D) which on hydrolysis gives again gas (B)> Identify (B), (C) and (D).
(1)
(2)
(3)
(4)
Property of all the alkaline earth metals that increases with their atomic number is :
(A) Solubility of their carbonates
(B) Thermal stability of their sulphates
(C) Ionisation energy
(D) Electronegativity
Which of the following acts as an oxidizing as well as a reducing agent?
(1)
(2)
(3)
(4)
A metal [X] heating on nitrogen gas gives [Y]. [Y] on treatment with gives a colourless gas which when passed through solution gives a blue colour. [Y] is-
1.
2.
3.
4.
The correct relation about the density of Na and K is
1. Na > K
2. Na = K
3. K > Na
4. Li > K
In ionic radius of is more while atomic radius of is –
(1) Less than
(2) More than
(3) Equal to
(4) None of these
Lattice energy is lowest for –
1. LiF
2. NaCl
3. KBr
4. CsI
Which of the following halides has the highest melting point-
(A) NaCl
(B) KCl
(C) NaBr
(D) NaF
Alkaline earth metals form hydrated crystalline solids such as . This is due to-
(1) Smaller ionic size
(2) Increased charge on ions
(3) Higher hydration enthalpies
(4) High oxidation potential
Magnesium can be prepared by heating-
(1) with CaO at 1775 K
(2) with at 1775 K
(3) with under pressure
(4) MgO with at ordinary temperature
A chloride dissolves appreciably in cold water. When placed in a platinum wire in Bunsen flame no distinctive colour is noticed. Which cation could be present –
(1)
(2)
(3)
(4)
Which of the following is a false statement-
(1) Sodium oxide is more basic then magnesium oxide.
(2) Beryllium oxide is amphoteric
(3) The thermal stability of beryllium carbonate is more than that of calcium carbonate
(4) Beryllium is amphoteric
Which alkali metal has the lowest melting point and exists as a liquid at 30 degree temp–
(1) Na
(2) K
(3) Rb
(4) Cs
Two metals X and Y form covalent halides. Both halides can act as Lewis acids and a catalyst in Friedel Crafts reaction. Halide of X is polymer in the solid state and a dimer in the vapour state which decomposes to monomer at 1200 K. However, halide of Y is a dimer in vapour state and becomes ionic in polar solvent. X and Y are respectively.
(1) Be, Al
(2) Al, Be
(3) Be, Ca
(4) Mg, Ca
Solubility of sulphates in water decreases from to . It is due to the fact that –
(1) Ionic nature increases
(2) Size of ion increases
(3) Lattice energy decrease
(4) Hydration enthalpy of ions decreases
Alkali metal ions are-
1. Diamagnetic and coloured.
2. Diamagnetic and colourless.
3. Paramagnetic and coloured.
4. Paramagnetic and colourless.
A compound X on heating gives a colourless gas. The residue is dissolved in water to obtain Y. Excess is bubbled through an aqueous solution of Y, and Z is formed. Z on gentle heating gives back X. The compound X is-
1.
2.
3.
4.
A compound insoluble in acetic acid is -
1. Calcium oxide.
2. Calcium carbonate.
3. Calcium oxalate.
4. Calcium hydroxide.
Assertion : s-block elements do not occur free in nature
Reason: s-block elements are highly electropositive in nature.
1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true, but R is not the correct explanation of A.
3. A is true, but R is false.
4. Both A and R are false.