What happens when: (write chemical equations only ) (a) Anhydrous `AlCl_(3)` is exposed to atmosphere. (b) `AlCl_(3)` dissolves in aqueous sodium hydroxide (excess)
1 Answers
Write the balanced chemical equations for the following. (i)Hypophosphorous acid is heated. (ii) Sodium chlorate reacts with sulphur dioxide in dilute
(i) `underset("Phosphorus acid") (4H_(3)PO_(3)) overset("heat") to underset("Phosphoric acid")(3H_(3)PO_(4))+ underset("Phosphine")(PH_(3))` (ii)` Xe + PtF_(6) overset("hot") to Xe^(+) [PtF_(6)]^(-)`
2 Answers 1 views
Write the balanced chemical equations for the following reactions (i) A mixture of potassium dichromate and sodium chloride is heated with concentrate
(a) `({:(K_(2)Cr_(2)O_(7)+2H_(2)SO_(4)to KHSO_(4)+2CrO_(3)+H_(2)O),(NaCl+H_(2)SO_(4)to NaHSO_(4)+HCLxx4),(2CrO_(3)+4HCl to 2CrO_(2)Cl_(2)+2H_(2)O):})/(K_(2)Cr_(2)O_(7)+4NaCl+6H_(2)SO_(4) to 2CrO_(2)Cl_(2)+4NaHSO_(4)+2KHSO_(4)+3H_(2)O)`
2 Answers 1 views
Coagulation value of the electrolytes `AlCl_(3)` and NaCl for `As_(2)S_(3)` sol are 0.093 and 52 respectively. How many times `AlCl_(3)` has greater c
Correct Answer - C `("coagulation power of"AlCl_3)/("coagulation power of"NaCl)=("coagulation value of"NaCl)/("coagulation value of"AlCl_3)=52/0.093~~560`
2 Answers 1 views
Statement-1:Sodium chloride is added during electrolysis of fused anhydrous magnesium chloride. Statement-2:Anhydrous magnesium chloride is obtained b
Correct Answer - C S-1:It lowers the fusion temperature of `MgCl_2` and provide conductivity to the elecrolyte. S-2: `MgCl_2. 6H_2O` is calcined in a stream of dry HCl gas to have...
2 Answers 1 views
Which of the above-mentioned statements/s is/are TRUE? A. only 1 B. only 2 C. only 3 and 4 D. only 1, 2 and 4
D. only 1, 2 and 4
2 Answers 1 views
What happens when : (write only chemical reactions) (a) iodine is treated with `SnCl_(2)`. (b) carbondioxide is passed through a concertrated aqueous
(a)`2SnCl_(2)+l_(2)to2SnCl_(2)l_(2)toSnCl_(4)+Snl_(4)` (b)`NaCl+NH_(4)OH+CO_(2)toNAHCO_(3)+NH_(4)Cl` ( c)`Pb_(3)O_(4)+4HNO_(3) to 2Pb(NO_(3))_(2)+PbO_(2)+2H_(2)O` (d)`Sn+10HNO_(3)`(dilute)`to 4Sn(NO_(3))_(2)+NH_(4)NO_(3)+3H_(2)O`
2 Answers 1 views
A white crystalline substance dissolves in water.On passing `H_(2)S` in this solution, a black precipitate is obtained.The black precipitate dissolves
Correct Answer - C `Pb^(2+)+H_(2)StoPbSdarr("black")+2H^(+), 3PbS+8HNO_(3)to3Pb(NO_(3))_(2)+2NOuarr+3Sdarr+4H_(2)O` `Pb^(2+)+SO_(4)^(2-) to PbSO_(4) darr` (white)
2 Answers 1 views
Benzene reacts with n-propyl chloride in the presence of anhydrous `AlCl_(3)` to give predominantly
Correct Answer - B Propyl carbonium ion, `CH_(3)CH_(2)overset(+)CH_(2)` is primary carbonium ion, it rearranges to the more stable secondary carbonium ion `CH_(3)overset(+)CHCH_(2)` which then reacts to form isopropylbenzene. `underset("Propyl carbonium ion"(1^(@))(CH_(3)-underset(H)underset(|)(C...
2 Answers 1 views
In the presence of a small amount of phosphorous, aliphatic carboxylic acids react with chlorine or bromine to yield a compound in which `alpha`- hydr
Correct Answer - B `CH_(3)-underset(O)underset(||)C-OHoverset(Red P+Cl_(2))rarrCl-CH_(2)-underset(O)underset(||)C-OH`
2 Answers 1 views
One mole of anhydrous `MgCl_(2)` dissolves in water and librates `25 cal//mol` of heat. `Delta H_("hydration")` of `MgCl_(2)=30 cal//mol`. Heat of dis
Correct Answer - A `MgCl_(2).H_(2)O rarrMgCl_(2)(aq)Delta H_(1)= ?` `MgCl_(2)(aq)rarrMg^(2+)(aq)+2Cl^(-)(aq)Delta H_(2)= -30 cal//mol` `MgCl_(2)(s)rarrMg^(2+)(aq)+2Cl^(-1)(aq)Delta H_(3)= -25 cal//mol` `Delta H_(1)+Delta H_(2)=Delta H_(3)` `Delta H_(1)=Delta H_(3)-Delta H_(2)= -25+30= +5 cal//mol`
2 Answers 2 views