Which of the following bonds are weakest in nature?
Hydrogen bond
Bond strength is measured by the energy needed to break the bond. Covalent single, double and triple bonds are intramolecular and very strong — typical C–C, C=C and C≡C bond energies are roughly \(347,\ 614\ \text{and}\ 839\ \text{kJ/mol}\) respectively.
A hydrogen bond is an intermolecular attraction between an H bonded to a highly electronegative atom (N, O, F) and another electronegative atom. Its energy is only about \(10\text{–}40\ \text{kJ/mol}\) — an order of magnitude weaker than any covalent bond listed. Hence the hydrogen bond is the weakest.
Fire extinguishers emit which gas?
In the following reaction, fill in the blank.
Acid + Base → _______ + Water
Which of the following is a characteristic of an exothermic reaction?
Ozone is an ______ of oxygen.
What is the common characteristic of the elements of the same group in the periodic table?
Which amongst the following is not a cation?
What is the chemical name of saltpetre?
The reaction of Copper Sulphate and Iron produces Iron Sulphate and __________.
What is the bond angle (in degrees) in the structure of a benzene molecule?
Fire extinguishers emit which gas?