Order of reactivity of halogen acids towards an alcohol is

• HCl > HBr > HI

• HBr > HI > HCl

• HI > HBr > HCl

• HI > HCl > HBr

What are the products formed when ammonia reacts with excess chlorine?

• N₂ and NCl₃

• NCl₃ and HCl

• N₂ and NH₄Cl

• N₂ and HCl

Compound X is anhydride of sulphuric acid. The number of σ-bonds and the number of π-bonds presentin X are, respectively :

• 3,3

• 4,2

• 2,4

• 4,3

Which one of the following is a correct pair with respect to molecular formula of xenon compound and hybridization state of xenon in it?

• XeF₄, sp³

• XeF₂, sp

• XeF₂, sp³d

• XeF₄, sp²

The oxidation state of Xe in XeO₃ and the bond angle in it respectively are:

• +6, 109°

• +8, 103°

• +6, 103°

• +8, 120°

Fluorosis disease is caused due to the reaction of with excess of fluoride in the body.

• Ca

• Mg

• Fe

• K

Two oxides of nitrogen, NO and NO₂ react together at 253K and form a compound of nitrogen X. X reacts with water to yield another compound of nitrogen Y. The shape of the anion of Y molecule is :

• tetrahedral

• triangular planar

• square planar

• pyramidal

Chlorine atom, in its third excited state, reacts with fluorine to form a compound X. The formula and shape of X are :

• ClF₅,  pentagonal

• ClF₄, tetrahedral

• ClF₄, pentagonal bipyramidal

• ClF₇, pentagonal bipyramidal

319.

In Fischer-Ringe's method of separation of nobles gas mixture from air ....... is used

• 90% CaC₂ + 10% CaCl₂

• coconut charcoal

• soda lime + potash solution

• 90% CaCO₃ + 10% urea

In the Dewar's method of separation of noble gases, the mixture of noble gases is kept in contact with coconut charcoal at 173 K. Which one of the following gaseous mixtures is not adsorbed on to the charcoal?

• Ar, Kr

• Xe, Ar

• He, Ne

• Xe, Kr