Email
Chat with tutors
logo

Ask Questions, Get Answers

X
 

Answers posted by mosymeow_1

352
answers
0
best answers
0 votes
An inorganic salt when heated evolves a coloured gas which bleaches moist litmus paper. The evolved gas is
answered Feb 1, 2014
Answer: $Cl_2$ $Cl_2$ is a greenish yellow gas which bleaches litmus paper by oxidation$Cl_2 +...
0 votes
Heating of oxalic acid with conc. $H_2SO_4$ gives
answered Feb 1, 2014
Answer: $CO + CO_2$ When oxalic acid is heated in the presence of concentrated sulphuric acid, oxali...
0 votes
A test tube containing a nitrate and another containing a bromide and $MnO_2$ are treated with conc. $H_2SO_4$. The brown fumes evolved are passed through water. The water will be coloured by
answered Feb 1, 2014
Answer: the bromide  $NO^-_3$ gives $NO_3$ with conc. $H_2SO_4$ which on pasing through water ...
0 votes
When a salt is heated with dil $H_2SO_4$ and $KMnO_4$ solution, the pink colour of $KMnO_4$ is discharged, the mixture contains:
answered Feb 1, 2014
Answer: Sulphite  $SO_3^{2-}$ reduces $KMnO_4$ and colour of $KMnO_4$ is discharged.$5SO_3^{2-...
0 votes
When borax is heated in a platinum loop, the transparent bead formed contains
answered Feb 1, 2014
Answer: Sodium metaborate + $B_2O_3$  $Na_2B_4O_7.10H_2O$ (Borax) $\xrightarrow[Pt. loop]{\Del...
0 votes
The most suitable indicator for the titrations of $Ba(OH)_2$ against HI is
answered Feb 1, 2014
Toolbox:Suitable indicator for strong acid-strong base titrations are phenolphthalein & methyl o...
0 votes
If $pK_{in}$ of an indicator is 10.5, the pH transition range for which it is most suitable is
answered Feb 1, 2014
Answer: 9.5-11.5  The pH transition range for an indicator = $pK_{in}\pm 1 = 10.5 \pm 1$Theref...
0 votes
The most suitable indicator for the titration of HCOOH against NaOH is
answered Feb 1, 2014
Toolbox:Indicator for strong acid-strong base titrations: phenolphthalein, methyl orangeIndicator fo...
0 votes
Completion of diazotisation can be checked with
answered Feb 1, 2014
Answer: Starch KI paper  Completion of diazotisation can be checked with starch KI paper. Exce...
0 votes
$C_6H_5OH$ and $C_2H_5OH$ can be distinguished by
answered Feb 1, 2014
Answer: Litmus test $C_6H_5OH$ (phenol) and $C_2H_5OH$ (ethanol) can be distinguished by litm...
0 votes
Which of the following compound will give blood red colour while doing the Lassigne's test for N?
answered Feb 1, 2014
Answer: $H_2N(C_6H_4)SO_3H$  $H_2N(C_6H_4)SO_3H$ contains N, S and C. During fusion with sodium...
0 votes
Presence of nitrogen in which of the following compound cannot be detected by Lassaigne's test?
answered Jan 30, 2014
Answer: HydrazineAs no carbon is present in hydrazine, no NaCN is formed during sodium fusion test.
0 votes
Flame test is not given by
answered Jan 28, 2014
Answer: $Be^{2+}$ ions $Be^{2+}$ ions does not give flame test because of its high ionisation e...
0 votes
$[X] + H_2SO_4 \longrightarrow [Y]$ colourless with irritating smell. $[Y] + K_2Cr_2O_7 + H_2SO_4 \longrightarrow$ Green solution. [X] and [Y] are
answered Jan 28, 2014
Answer: $SO_3^{2-}, SO_2$ $[X]=SO_3^{2-}$ ion, $[Y]=SO_2$$SO_3^{2-} + H_2SO_4 \longrightarrow S...
0 votes
The ion that cannot be precipitated by both $HCl$ and $H_2S$
answered Jan 28, 2014
Answer: $Sn^{2+}$ $Pb^{2+}$ and $Ag^+$ can be precipitated both by $HCl$ and $H_2S$. $Cu^{2+}$ ...
0 votes
Potassium cyanide is used for separating
answered Jan 28, 2014
Answer: $Co^{2+}$ and $Ni^{2+}$ When heated with KCN solution $Ni^{2+}$ forms potassium nickelc...
0 votes
How do we differentiate between $Fe^{3+}$ and $Cr^{3+}$ in groupIII?
answered Jan 28, 2014
Toolbox:$OH^-$ ions precipitate both $Fe^{3+}$ and $Cr^{3+}$ as their hydroxides. However, $Cr(OH)_3...
0 votes
When a substance 'A' reacts with water, it produces a combustible gas 'B' and a solution of substance 'C' in water. When another substance 'D' reacts with this solution of 'C', it also produces the same gas 'B' on warming but 'D' can produce gas 'B' on reaction with dilute sulphuric acid at room temperature. 'A' imparts a deep golden yelow colour to the smokeless flame of bunsen flame. 'A', 'B' , 'C' & 'D' are respectively
answered Jan 28, 2014
Answer: $Na, H_2, NaOH, Zn$     When Na reacts with water, it produces a ...
0 votes
Three separate samples of a solution of a single salt gave these results. One formed a white ppt. with excess ammonia solution, one formed a white ppt. with dil. NaCl solution and one formed a black ppt. with $H_2S$. The salt could be:
answered Jan 28, 2014
Answer: $Pb(NO_3)_2$ $Pb(NO_3)_2 + 2NH_4OH \longrightarrow Pb(OH)_2 \downarrow (\text{white pp...
0 votes
The only cations present in a slightly acidic solution are $Fe^{3+}, Zn^{2+}$ and $Cu^{2+}$. The reagent that when added in excess to this solution would identify and separate $Fe^{3+}$ in one step is
answered Jan 28, 2014
Answer: 6M $NH_3$$Fe^{3+} + Zn^{2+} + Cu^{2+} \xrightarrow{\text{6M } NH_3} Fe(OH)_3 \text{(brown pp...
0 votes
When $K_2Cr_2O_7$ crystals are heated with conc. HCl, the gas evolved is
answered Jan 28, 2014
Answer: $Cl_2$ $K_2Cr_2O_7 + 8HCl \longrightarrow 2KCl + 2CrCl_3 + 4H_2O + 3[O]${$2HCl + [O] \l...
0 votes
A pale green crystalline metal salt $M$ dissolves freely in water. It gives a brown precipitate on addition of aqueous $NaOH$. The metal salt solution also gives a black precipitate on bubbling $H_2S$ in aqueous medium. An aqueous solution of the metal salt decolourises the pink colour of the permanganate solution. The metal in the metal salt solution is
answered Jan 28, 2014
Answer: Iron Pale green salt contains a mixture of $Fe^{2+}$ and $Fe^{3+}$ ions$Fe^{3+} + 3OH^- \lon...
0 votes
Which of the following salt would give $SO_2$ with hot and dil. $H_2SO_4$ and also decolourise $Br_2$ water?
answered Jan 28, 2014
Answer: $Na_2SO_3$$Na_2SO_3 + H_2SO_4 \longrightarrow Na_2SO_4 + SO_2 \uparrow + H_2O$Sodium sulphat...
0 votes
An aqueous solution of coloureless metal sulphate M gives a white precipitate with $NH_4OH$. This was soluble in excess of $NH_4OH$. On passing $H_2S$ through this solution a white ppt is formed. The metal M in the salt is
answered Jan 28, 2014
Answer: Zn$Zn^{2+} + 2NH_4OH \longrightarrow Zn(OH)_2$ (White ppt.)$ + 2NH_4^+$$Zn(OH)_2 + 2NH_4OH \...
0 votes
A metal salt solution forms a yellow precipitate with potassium chromate in acetic acid, a white precipitate with dilute $H_2SO_4$ but gives no precipitate with sodium chloride or iodide, it is
answered Jan 28, 2014
Answer: Barium carbonate $BaCO_3 + 2CH_3COOH \longrightarrow Ba(CH_3COO)_2 + CO_2 + H_2O$$Ba(CH_3COO...
0 votes
$K_4[Fe(CN)_6]$ can be used to detect one or more out of $Fe^{2+}, Fe^{3+}, Zn^{2+}, Cu^{2+}, Cd^{2+}$
answered Jan 28, 2014
Answer: All but $Fe^{2+}$ $2ZnCl_2 + K_4[Fe(CN)_6] \xrightarrow{CH_3COOH} Zn_2[Fe(CN)_6]_3 ...
0 votes
$NH_4CNS$ can be used to test one or more out of $Fe^{3+}, Co^{2+}, Cu^{2+}$
answered Jan 28, 2014
Answer: all$CoCl_2 + 4NH_4CNS \overset{ether}{\longrightarrow} (NH_4)_2[Co(CNS)_4] \text{(Blue colou...
0 votes
Potassium ferrocyanide is used in the detection of
answered Jan 28, 2014
Answer: Both $Cu^{2+}$ & $Fe^{3+}$ ions Both $Cu^{2+}$ & $Fe^{3+}$ ions can be detected...
0 votes
In the fourth group, $Mn(OH)_2$ on heating with $PbO_2$ and conc. $HNO_3$ gives pink colour due to the formation of
answered Jan 28, 2014
Answer: $KMnO_4$ $Mn(OH)_2 + 2HNO_3 \longrightarrow Mn(NO_3)_2 + 2H_2O$ On heating,$2Mn(NO_3)_...
0 votes
To aviod the precipitation of hydroxide of $Ni^{2+}, Co^{2+}, Mn^{2+}$ along with those of the third group cations, the solutions should be
answered Jan 28, 2014
Answer: Heated with excess of ammonium chloride Function of strong electrolyte $NH_4Cl$ is to ...
0 votes
Mark the compound which turns black with $NH_4OH$
answered Jan 28, 2014
Answer: Mercurous Chloride $Hg_2Cl_2 + 2NH_4OH \longrightarrow [NH_2-Hg-Hg-Cl]$ (unstable comp...
0 votes
Chromyl chloride vapours are dissolved in water and acetic acid and lead acetate solution is added, then
answered Jan 28, 2014
Answer: A yellow ppt. will be obtained  $CrO_2Cl_2 + 2H_2O \longrightarrow H_2CrO_4 + 2HCl$Chr...
0 votes
In a combination of $NO_3^-, Br^-$ and $I^-$ present in a mixture, $Br^-$ and $I^-$ interfere in the ring test for $NO_3^-$. These are removed by adding a solution of
answered Jan 28, 2014
Answer: $Ag_2SO_4$ $2Br^- + Ag_2SO_4 \longrightarrow 2AgBr \downarrow + SO_4^{2-}$$2I^- + Ag_2S...
0 votes
$BaCl_2$ solution gives a white ppt. with a solution of a salt, which dissolves in dil. HCl with the evolution of a colourless, pungent smelling gas. The acid radical in the salt is
answered Jan 28, 2014
Answer: $SO_3^{2-}$ $SO_3^{2-} + Ba^{2+} \longrightarrow BaSO_3 \downarrow$ (White ppt.)$BaSO_...
0 votes
To a solution of a salt, $MgSO_4$ solution is added and white ppt. appears only on heating. The acid radical in the salt is
answered Jan 28, 2014
Answer: $HCO_3^-$ $2NaHCO_3 + MgSO_4 \longrightarrow Mg(HCO_3)_2 + H_2O + CO_2$saltOn heating,...
0 votes
On heating a mixture of potassium dichromate and sodium chloride with concentrated sulphuric acid in a dry test tube, the compound formed
answered Jan 28, 2014
Answer: Chromyl chloride $4NaCl(s) + K_2Cr_2O_7(s) + 3H_2SO_4(l) \overset{\Delta}{\longrightarr...
0 votes
Nitrate is confirmed by ring test. The brown colour of the ring test is due to the formation of
answered Jan 28, 2014
Answer: $FeSO_4.NO$ $NaNO_3 + H_2SO_4 \longrightarrow NaHSO_4 + HNO_3$Now, $4FeSO_4 \text{(Ferr...
0 votes
Production of a green edged flame on igniting the vapours evolved by heating a given inorganic salt with few mL of ethyl alcohol and conc. $H_2SO_4$ indicates the presence of a
answered Jan 26, 2014
Toolbox:Ethyl Borate is Volatile and burns with a green edged flame.Answer: Borate $NaBO_3 + 2...
0 votes
NaCl , NaBr and NaI mixture on heating with conc. $H_2SO_4$ gives gases respectively
answered Jan 26, 2014
Answer: $HCl, Br_2, I_2$$NaCl + H_2SO_4 \overset{\Delta}{\longrightarrow} NaHSO_4 + HCl \uparrow $$H...
0 votes
A salt on reaction with dil. $H_2SO_4$ gives a reddish brown gas. The salt is
answered Jan 26, 2014
Answer: $KNO_2$ $2KNO_2 + H_2SO_4 \longrightarrow K_2SO_4 + HNO_2$$3HNO_2 \longrightarrow HNO_3...
0 votes
A few drops of conc $H_2SO_4$ is added to the solution of $FeSO_4$ in water to
answered Jan 26, 2014
Answer: prevent salt hydrolysisA few drops of conc. $H_SO_4$ added to a solution of $FeSO_4$ [or $Al...
0 votes
Which of the following test can be used to distinguish between phenol and cyclohexanol?
answered Jan 26, 2014
Answer: $Br_2$ water test   phenol         ...
0 votes
In Lassaigne's test when both N and S are present, blood red colour is due to the formation of
answered Jan 26, 2014
Nitrogen, Sulphur and halogens, if present in an organic compound are detected by Lassaigne's test...
0 votes
On heating ammonium dichromate the gas evolved is
answered Jan 26, 2014
Answer: Nitrogen   $(NH_4)_2Cr_2O_7 \overset{\Delta} {\longrightarrow} Cr_2O_3 + 4H_2O + ...
0 votes
Which one among the following pairs of ions cannot be separated by $H_2S$ in dilute hydrochloric acid?
answered Jan 26, 2014
Answer: $Bi^{3-}, Sn^{4+}$   $Bi^{3-}$ and $Sn^{4+}$ belong to III group and thus cannot ...
0 votes
The phenomenon in which white transparent crystal changes into white powder is called
answered Jan 26, 2014
Toolbox: In chemistry, efflorescence is the loss of water (or a solvent) of crystallizati...
0 votes
Which of the following is not precipitated as sulphide by passing $H_2S$ in the presence of conc. HCl?
answered Jan 26, 2014
Answer: Cadmium Solubility product of CdS is greater than the other sulphides of group II, it is...
0 votes
A one litre flask is full of brown bromine fumes. The intensity of brown colour of vapour will not decrease appreciably on adding to the flask some
answered Jan 26, 2014
Marble $(CaCO_3)$ does not react, adsorb, adsorb or dissolve $Br_2$. So the intensity of brown colou...
0 votes
A mixture of two salts is not water soluble but dissolves completely in dil. HCl to form a colourless solution. The mixture could be
answered Jan 26, 2014
Answer: $BaCO_3$ and $ZnS$ $BaCO_3$ + $ZnS$ mixture dissolves in HCl but is insoluble in water. ...
0 votes
Which of the following is soluble in yellow ammonium sulphide?
answered Jan 26, 2014
Answer: SnS $SnS + (NH_4)_2S +S \longrightarrow (NH_4)_2SnS_3$ $(NH_4)_2S$ is yellow ammonium ...
Page:
Home Ask Tuition Questions
Practice
Your payment for is successful.
Continue
...