The correct group of halide ions which can be oxidised by oxygen in acidic medium is :
The covalency and oxidation state respectively of boron in $\left[\mathrm{BF}_{4}\right]^{-}$, are :
The incorrect statement from the following for borazine is :
Given below are two statements :
Statement I : Boron is extremely hard indicating its high lattice energy.
Statement II : Boron has highest melting and boiling point compared to its other group members.
In the light of the above statements, choose the most appropriate answer from the options given below :
Given below are two statements :
Statement I : $\mathrm{SbCl}_{5}$ is more covalent than $\mathrm{SbCl}_{3}$
Statement II: The higher oxides of halogens also tend to be more stable than the lower ones.
In the light of the above statements, choose the most appropriate answer from the options given below :
Which one of the following pairs is an example of polar molecular solids?
One mole of $\mathrm{P}_{4}$ reacts with 8 moles of $\mathrm{SOCl}_{2}$ to give 4 moles of $\mathrm{A}, x$ mole of $\mathrm{SO}_{2}$ and 2 moles of $\mathrm{B} . \mathrm{A}, \mathrm{B}$ and $x$ respectively are :
For compound having the formula $\mathrm{GaAlCl}_{4}$, the correct option from the following is :
Match List I with List II
| LIST I Name of reaction |
LIST II Reagent used |
||
|---|---|---|---|
| A. | Hell-Volhard-Zelinsky reaction | I. | $NaOH + {I_2}$ |
| B. | Iodoform reaction | II. | (i) $Cr{O_2}C{l_2},C{S_2}$ (ii) ${H_2}O$ |
| C. | Etard reaction | III. | (i) $B{r_2}$ / red phosphorus (ii) $H_2O$ |
| D. | Gatterman-Koch reaction | IV. | $CO,HCl,$, anhyd. $AlC{l_3}$ |
Choose the correct answer from the options given below:
The correct order of bond enthalpy ($\mathrm{kJ~mol^{-1}}$) is :
For electron gain enthalpies of the elements denoted as $\Delta_{\mathrm{eg}} \mathrm{H}$, the incorrect option is :
Given below are two statements:
Statement I : Chlorine can easily combine with oxygen to form oxides; and the product has a tendency to explode.
Statement II : Chemical reactivity of an element can be determined by its reaction with oxygen and halogens.
In the light of the above statements, choose the correct answer from the options given below :
Statement I: Upon heating a borax bead dipped in cupric sulphate in a luminous flame, the colour of the bead becomes green
Statement II: The green colour observed is due to the formation of copper(I) metaborate
In light of the above statements, choose the most appropriate answer from the options given below :
During the borax bead test with $\mathrm{CuSO_4}$, a blue green colour of the bead was observed in oxidising flame due to the formation of :
"A" obtained by Ostwald's method involving air oxidation of NH$_3$, upon further air oxidation produces "B", "B" on hydration forms an oxoacid of Nitrogen along with evolution of "A". The oxoacid also produces "A" and gives positive brown ring test.
Identify A and B, respectively :
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Carbon forms two important oxides - CO and CO$_2$. CO is neutral whereas CO$_2$ is acidic in nature
Reason R : CO$_2$ can combine with water in a limited way to form carbonic acid, while CO is sparingly soluble in water
In the light of the above statements, choose the most appropriate answer from the options given below :
A. Ammonium salts produce haze in atmosphere.
B. Ozone gets produced when atmospheric oxygen reacts with chlorine radicals.
C. Polychlorinated biphenyls act as cleansing solvents.
D. 'Blue baby' syndrome occurs due to the presence of excess of sulphate ions in water.
Choose the correct answer from the options given below :
Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from :
Reaction of thionyl chloride with white phosphorus forms a compound [A], which on hydrolysis gives [B], a dibasic acid. [A] and [B] are respectively :
Compound A reacts with NH$_4$Cl and forms a compound B. Compound B reacts with H$_2$O and excess of CO$_2$ to form compound C which on passing through or reaction with saturated NaCl solution forms sodium hydrogen carbonate. Compound A, B and C, are respectively :
$\mathrm{K_2Cr_2O_7}$ paper acidified with dilute $\mathrm{H_2SO_4}$ turns green when exposed to :
Which of the Phosphorus oxoacid can create silver mirror from $\mathrm{AgNO_3}$ solution?
In liquation process used for tin (Sn), the metal :
Given below are two statements.
Statement I : Stannane is an example of a molecular hydride.
Statement II : Stannane is a planar molecule.
In the light of the above statement, choose the most appropriate answer from the options given below.
When borax is heated with $\mathrm{CoO}$ on a platinum loop, blue coloured bead formed is largely due to :
Dinitrogen is a robust compound, but reacts at high altitudes to form oxides. The oxide of nitrogen that can damage plant leaves and retard photosynthesis is :
White phosphorus reacts with thionyl chloride to give :
Concentrated $\mathrm{HNO}_{3}$ reacts with Iodine to give :
Dinitrogen and dioxygen, the main constituents of air do not react with each other in atmosphere to form oxides of nitrogen because :
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Boron is unable to form $\mathrm{BF}_{6}^{3-}$.
Reason (R) : Size of B is very small.
In the light of the above statements, choose the correct 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 : Activated charcoal adsorbs SO2 more efficiently than CH4.
Reason R : Gases with lower critical temperatures are readily adsorbed by activated charcoal.
In the light of the above statements, choose the correct answer from the options given below.
Given below are two statements.
Statement I: The chlorides of $\mathrm{Be}$ and $\mathrm{Al}$ have Cl-bridged structure. Both are soluble in organic solvents and act as Lewis bases.
Statement II: Hydroxides of $\mathrm{Be}$ and $\mathrm{Al}$ dissolve in excess alkali to give beryllate and aluminate ions.
In the light of the above statements, choose the correct answer from the options given below.
Which oxoacid of phosphorous has the highest number of oxygen atoms present in its chemical formula?
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion : Boric acid is a weak acid.
Reason R : Boric acid is not able to release $\mathrm{H}^{+}$ ion on its own. It receives $\mathrm{OH}^{-}$ ion from water and releases $\mathrm{H}^{+}$ ion.
In the light of the above statements, choose the most appropriate answer from the options given below.
Match List - I with List - II.
| List I (Processes / Reactions) |
List II (Catalyst) |
||
|---|---|---|---|
| (A) | 2SO$_2$(g) + O$_2$(g) $ \to $ 2SO$_3$(g) | (I) | Fe(s) |
| (B) | 4NH$_3$(g) + 5O$_2$(g) $ \to $ 4NO(g) + 6H$_2$O(g) | (II) | Pt(s) $ - $ Rh(s) |
| (C) | N$_2$(g) + 3H$_2$(g) $ \to $ 2NH$_3$(g) | (III) | V$_2$O$_5$ |
| (D) | Vegetable oil(l) + H$_2$ $ \to $ Vegetable ghee(s) | (IV) | Ni(s) |
Choose the correct answer from the options given below :
Borazine, also known as inorganic benzene, can be prepared by the reaction of 3-equivalents of "$X$" with 6-equivalents of "$Y$". "$X$" and "$Y$", respectively are :
The total number of acidic oxides from the following list is
NO, N2O, B2O3, N2O5, CO, SO3, P4O10
Match List I with List II:
| List I | List II | ||
|---|---|---|---|
| (A) | Sulphate | (I) | Pesticide |
| (B) | Fluoride | (II) | Bending of bones |
| (C) | Nicotine | (III) | Laxative effect |
| (D) | Sodium arsinite | (IV) | Herbicide |
Choose the correct answer from the options given below :
Match List I with List II
| List I | List II | ||
|---|---|---|---|
| (A) | N$_2$(g) + 3H$_2$(g) $ \to $ 2NH$_3$(g) | (I) | Cu |
| (B) | CO(g) + 3H$_2$(g) $ \to $ CH$_4$(g) + H$_2$O(g) | (II) | Cu/ZnO $ - $ Cr$_2$O$_3$ |
| (C) | CO(g) + H$_2$(g) $ \to $ HCHO(g) | (III) | Fe$_x$O$_y$ + K$_2$O + Al$_2$O$_3$ |
| (D) | CO(g) + 2H$_2$(g) $ \to $ CH$_3$OH(g) | (IV) | Ni |
Choose the correct answer from the options given below :
The geometry around boron in the product 'B' formed from the following reaction is
$ \begin{aligned} &\mathrm{BF}_{3}+\mathrm{NaH} \stackrel{450 \mathrm{~K}}{\rightarrow} \mathrm{A}+\mathrm{NaF} \\\\ &\mathrm{A}+\mathrm{NMe}_{3} \rightarrow \mathrm{B} \end{aligned} $
The interhalogen compound formed from the reaction of bromine with excess of fluorine is a :
A $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{}^{573\,K}} $ Red phosphorus $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{under\,pressure}^{heat\,;\,803\,K}} $ B
Red phosphorus is obtained by heating "A" at 573 K, and can be converted to "B" by heating at 803 K under pressure.
A and B, respectively, are
Aqueous solution of which of the following boron compounds will be strongly basic in nature?
Sulphur dioxide is one of the components of polluted air. SO2 is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by SO2 is :
Match List-I with List-II.
| List-I (Metal) |
List-II (Application) |
||
|---|---|---|---|
| (A) | Cs | (I) | High temperature thermometer |
| (B) | Ga | (II) | Water repellent sprays |
| (C) | B | (III) | Photoelectric cells |
| (D) | Si | (IV) | Bullet proof vest |
Choose the most appropriate answer from the options given below :
The oxoacid of phosphorus that is easily obtained from a reaction of alkali and white phosphorus and has two P-H bonds, is :
Among the given oxides of nitrogen ; N2O, N2O3, N2O4 and N2O5, the number of compound/(s) having N - N bond is :
Which of the following oxoacids of sulphur contains "S" in two different oxidation states?
