List of top Chemistry Questions

Calculate the normality of a solution obtained on mixing 100 ml of $\frac{M}{10} H_2 SO_4 , 50 \, ml$ of $\frac{N}{2} HNO_3$ and $25 \, ml $ of $\frac{N}{5} HCl$ solutions.
A 100 mL flask contained \(H_2\) at 200 torr, and a 200 mL flask contained \(He\) at 100 torr. The two flask were then connected so that each gas filled their combined volume. Assume, no change in temperature, total pressure is
How many milliliters of water must be added to 50.0 mL of 10.0 M HNO3 to prepare 4.00 M HNO3?
The decreasing order of bond angles in $BF_{3} , NH_{3} , PF_{3}$ and $I_{3}{^{-}}$ is
The most polar compound among the following is :
Which of the following statements is false?
The oxidation states of $Cr$ in $ [Cr(H_2O)_6]Cl_3, [Cr(C_6H_6)_2]$, and $K_2[Cr(CN)_2(O)_2(O_2)(NH_3)]$ respectively are :
The ratio of mass percent of $C$ and $H$ of an organic compound $\left( C _{ X } H _{ Y } O _{ Z }\right)$ is $6: 1 .$ If one molecule of the above compound $\left( C _{ X } H _{ Y } O _{ Z }\right)$ contains half as much oxygen as required to burn one molecule of compound $C _{X} H_{Y}$ completely to $CO _{2}$ and $H _{2} O$. The empirical formula of compound $C _{ X } H _{ Y } O _{ Z }$ is
Two compounds I and II are eluted by column chromatography (adsorption of I > II). Which one of following is a correct statement ?
When $9.65\,A$ current was passed for $1.0\, hour$ into nitrobenzene in acidic medium, the amount of p-aminophenol produced is_____.
Hydrogen peroxide oxidises $[Fe(CN)6]^{4-}$ to $[Fe(CN)6]^{3-}$ in acidic medium but reduces $[Fe(CN)6]^{3-}$ to$[Fe(CN)6]^{4-}$ in alkaline medium. The other products formed are, respectively

The first step in producing pure lead from galena $(PbS)$ is as follows: $ 2{PbS}(s) + 3{O}_2(g) \longrightarrow 2{PbO}(s) + 2{SO}_2(g) $. 
All of the following are true concerning this reaction except:

Ammonia burns in air to form nitrogen dioxide and water. $4{NH}_3(g) + 7{O}_2(g) \longrightarrow 4{NO}_2(g) + 6{H}_2{O}(l) $ If 8 moles of $NH_3$ are reacted with 14 moles of $O_2$ in a rigid container with an initial pressure of 11 atm, what is the partial pressure of $NO_2$ in the container when the reaction runs to completion? (Assume constant temperature)

Choose the most appropriate options. Arrange the following in the decreasing order of basic character: I. p-toluidine II. N,N-dimethyl-p-toluidine III. p-nitroaniline IV. Aniline
Choose the most appropriate options. The magnetic moment of M^{x+} (atomic number = 25) is $\sqrt{5}$ BM. Then, the oxidation number x of M is:
The \( K_{sp} \) for Mn(OH)\(_2\) is \( 1.6 \times 10^{-13} \). What is the molar solubility of this compound in water?

Arrange the following compounds in the increasing order of their reactivity towards HCN: 
I. Acetaldehyde 
II. Acetone 
III. Di-tert-butyl ketone

Which species have delocalised electrons? 

Which one of the following electrolytes is most effective for the coagulation of $Fe(OH)_3$ sol?
What is the minimum number of moles of Pb(NO3) must be added to 0.10L of a solution that is 1.0M in MgCl2 and 1.0 M in KCl? The compound PbCl2 precipitates.
Compared to an electron with a principal quantum number of 1, an electron with a principal quantum number of 2 will have a

Which of the following are true statements? 
I. The heat capacity of a substance is the amount of heat that substance can hold per unit of temperature. 
II. The specific heat for a single substance is the same for all phases of that substance. 
III. When heat is added to a fluid, its temperature will change less if it is allowed to expand.

The following data was obtained for the reaction, 

Choose the most appropriate options. Identify the product B of the following reactions. 

Calculate the rate constant for the radioactive disintegration of an isotope that has a half-life of 6930 yr.