List of top Chemistry Questions

XeF$_4$ reacts with SbF$_5$ to form:
\[ [\text{XeF}_m]^{n+}[\text{SbF}_y]^{z-} \] What is $m+n+y+z$?

What happens when lyophilic sol is added to lyophobic sol. prevention from coagulation precipitation emulsion electrophoresis

How many statements are correct:

If there is no relation between rate constant and temperature, then activation energy is negative.
If the activation energy is zero, rate constant is temperature independent.
If rate constant increases with increase of temperature, activation energy is positive.
If rate constant decreases with increase in temperature, activation energy is negative.

The pair of lanthanides will exceptionally high 3^rd ionisation enthalpy than neighbouring elements:

Sulphur (S)-containing amino acids from the following are:
(a) Isoleucine
(b) Cysteine
(c) Lysine
(d) Methionine
(e) Glutamic acid

Select the correct order of electronegativity of the elements: B, C, At, S

Read the following two statements
Statement I: Ionic radius of Li+ is greater than Mg++
Statement II: Lithium and magnesium can't form superoxide

Reaction of thionyl chloride with white phosphorus forms a compound [A], which on hydrolysis gives [B], a dibasic acid $[ A ]$ and $[ B ]$ are respectively

Polymer which is named as orlon is:

Photochemical smog found mainly in

2[Au(CN)₂]^– + Zn $\to$ [Zn(CN)₄]^2– + 2Au$\downarrow$ is which of these
(A) Redox reaction
(B) Displacement reaction
(C) Combination reaction
(D) Decomposition reaction

Order of Covalent bond:
A. $KF > KI ; LiF > KF$
B. $KF < KI ; LiF > KF$
C. $SnCl _4> SnCl _2 ; CuCl > NaCl$
D. $LiF > KF ; CuCl <NaCl$
E. $KF < KI ; CuCl > NaCl$
Choose the correct answer from the options given below:

Which of the following have square pyramidal structure?

Choose the correct option.

The value of $log_{10}K$ for a reaction A ⇋ B is

(Given,

$\Delta H^{\circ}_{298K}$ = –54.67 kJ $mol^{-1}$

$\Delta H^{\circ}_{298K}$ = 10 kJ $mol^{-1}$

and R = 8.314 J $K^{-1}mol^{-1}$

2.303 × 8.314 × 298 = 5705)

In which of the following pairs of elements electron gain enthalpy difference is highest?

How many bromo products are formed when ethane is reacted with excess of Br₂ on heating?

If the radius of ground state hydrogen is 51 pm, find out the radius of 5th orbit of Li²⁺ ions. (closest integer)

Match the terms in Column-I with their description in Column-II and choose the correct option :

Column I		Column II
(i)	Vitamin A	a	Beri-beri
(ii)	Vitamin C (Ascorbic acid)	b	Cheilosis
(iii)	Riboflavin	c	Xerophthalmia
(iv)	Thiamine	d	Scurvy

How many moles of Ba₃(PO₄)₂ will be formed by the reaction of 5 moles of BaCl₂ and 3 moles of Na₃(PO₄).

Reaction of $BeO$ with ammonia and hydrogen fluoride gives A which on thermal decomposition gives $BeF _2$ and $NH _4 F$ What is ' $A ^{\prime}$ ?

Product (P) and (Q) are respectively

Match the terms in Column-I with their description in Column-II and choose the correct option:

Column I (Chemical reactions)		Column II (Enzymes used)
(i)	Glucose → CO₂+ Ethanol	a	Pepsin
(ii)	Sucrose→Glucose + Fructose	b	Diastase
(iii)	Starch →Maltose	c	Zymase
(iv)	Protein→Amino acids	d	Invertase

Number of ambidentate ligands in given complex [M_(en)(SCN)₄]: