Two or more different elements
A, B and D should be the ones you should check
Pure substances are substances which are homogenous in nature. They either consists of atoms of 1 kind or molecules of 1 kind. Atoms are seen in elements, where as molecules are seen in compounds like Acids, Bases, etc.
They mostly have fixed properties like boiling and melting points and are uniform in nature. :D
Answer:
The law of floatation is applied in all vessels which travel by waterways that include ships, submarines and ferry boats. It is also applied in some vessels which travel by air ways such as hot air balloon and air ship. Balloons of different colors and shapes are filled with lighter gas so that will float in air.
Answer:
Two molecules of hydrogen combine with two molecules of oxygen to form hydrogen peroxide. Hence, its chemical formula is H2O2. It is the simplest peroxide (since it is a compound with an oxygen-oxygen single bond). Hydrogen peroxide has basic uses as an oxidizer, bleaching agent and antiseptic