This video lecture from Group VA and Group VIA Elements (F.Sc. second year Chemistry) covers the oxides and oxy-acids of phosphorus. Phosphorus Acid is discussed in detail including its structure, preparation, physical and chemical properties. The reactions of phosphorus acid as a reducing agent are also covered. The dehydrating nature of phosphorus pentaoxide is also discussed as a continuation of the previous lecture. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.