Hydrogen peroxide (H₂O₂) is an oxidiser, commonly used as bleach. It is the simplest peroxide. Hydrogen peroxide is a clear liquid, slightly more viscous than water, that appears colourless in dilute solution. It is used as a disinfectant, antiseptic, oxidiser and as a propellant in rocketry.

Potassium hydroxide is an inorganic compound with the formula KOH. Its common name is caustic potash. It has many industrial and niche applications. Most applications exploit its reactivity towards acids and its corrosive nature. Potassium iodide is an inorganic compound with the chemical formula KI. This white salt is the most commercially significant iodide compound. It is used to loosen and break up mucus in the airways.  Potassium nitrate is a natural solid source of nitrogen. Major uses of potassium nitrate are in fertilisers, rocket propellants and fireworks. It is one of the constituents of gunpowder. Potassium oxide is an important compound used in fertilisers, ceramics, glass and optics.   

The thermal stability of the hydrides decreases from H₂O to H₂Po due to the increase in bond length and decrease in bond energy with increase in atomic size. H₂O > H₂S > H₂Se > H₂Te > H₂Po 

Calcium chloride behaves as an ionic halide and is solid at room temperature. Common applications include brine for refrigeration plants, ice and dust control on roads and desiccation. Potassium carbonate is a white salt, which forms a strongly alkaline solution. It is used in the production of soap and glass. Potassium chlorate is a white crystalline substance. It is the most common chlorate in industrial use. It is used as an oxidising agent as a disinfectant in safety matches, explosives and fireworks. Potassium chloride (KCl) is a metal halide salt composed of potassium and chlorine. In its pure state, it is odourless and has a white or colourless vitreous crystal appearance. The majority of potassium chloride produced is used for making fertilisers as the growth of many plants is limited by their potassium intake.

CO₂ gas should be use to decolourise the nitric acid.

Volatility increases from H₂O to H₂S and then decreases to H₂Po. H₂S > H₂Se > H₂Te > H₂Po > H₂O The least volatility and high boiling point of water is due to hydrogen bonds.

Oxygen is the second most electronegative element after fluorine.

Ozone essentially behaves as a powerful oxidising agent.

Carbon monoxide forms an irreversible complex with haemoglobin of blood. 

Hydrogen chloride is a polar molecule in which hydrogen is electropositive and oxygen is electronegative. So, electron density is more on chlorine atom.