Find out the number of waves made by a Bohr electron in once complete revolution in its 3rd orbit?

The two types of bond present in B₂H₆ are covalent and _______.

Using the VSEPR theory, identify the type of hybridization and draw the structure of OF₂. What are the oxidation states of O and F?

An LPG (liquefied petroleum gas) cylinder weighs 14.8 kg when empty. When full, it weighs 29.0 kg and shows a pressure of 2.5 atm. In the course of use at 27^o C, the weight of the full cylinder reduces to 23.2 kg. Find out the volume of the gas in cubic meters used up at the normal usage conditions find the final pressure inside the cylinder. Assume LPG to be n-butane with normal boiling point of 0^o C.