Oxygen (O₂) is an element, a pure substance. Milk is a colloid; brass is an alloy (mixture); sea water is a solution (mixture). Pure substances have fixed composition.
Explanation:
LPG (propane/butane) is odorless. A small amount of strong-smelling mercaptan (ethanethiol) is added to help detect gas leaks, preventing accidents. Natural gas also has odorant. Mercaptans contain sulfur, and their smell is detectable at very low concentrations. Calorific value, temperature, performance are unaffected. Safety is primary.
Explanation:
Ionic compounds consist of positive and negative ions held together by strong electrostatic forces of attraction (ionic bonds). A large amount of energy is required to overcome these forces, resulting in high melting and boiling points. They also conduct electricity when molten or in solution.
Explanation:
The thermite process involves the reduction of a metal oxide by aluminum powder, which is highly exothermic. It is used to extract metals like chromium, manganese, and iron from their oxides (e.g., Cr2O3 + 2Al -> 2Cr + Al2O3). It is also practically used for welding iron railway tracks.
No comments yet. Be the first to start the discussion!