Heavy water (D₂O) freezes at

Nascent hydrogen is prepared by

‘Syngas’ is a mixture of hydrogen with

In aqueous solution, hydrogen peroxide oxidizes H₂S to

The hydride ion is iso-electronic with

The oxide that gives H₂O₂ on treatment with dilute acid is

The molarity of a 100 mL solution containing 5.1 g of hydrogen peroxide is