Compressed natural gas is used in vehicles and is a cheap source of fuel.

The kinetic energy of particles is maximum in gas as the particles are free to roam with maximum speed as there is negligible force of attraction between the particle.

Liquefied petroleum gas is used for cooking food at the homes.

Thermal conduction takes place in all the states of matter as the energy is transferred through particles so transfer of heat takes place.

The three phases of water are ice (present in solid state),  water (present in liquid state) and steam (present in the gaseous state).

Oxygen and nitrogen are gases, bromine is liquid at room temperature. So $KMnO _4$ is solid at room temperature.

Particles move randomly in a gaseous state. Here nitrogen is the only substance which is in a gaseous state.

Iron has the highest density as the particles are closely packed and volume occupied is less which makes the density very high.

The general order of force of attraction is Solid > Liquid > Gas. 

A state of matter is also characterized by phase transitions. A phase transition indicates a change in structure and can be recognized by an abrupt change in properties. A distinct state of matter can be defined as any set of states distinguished from any other set of states by a phase transition.

The three states of matter are classified on the basis of differences of certain physical properties such as physical existence; solids are physically hard, they have fixed shape and size. Liquids do not have any fixed shape and size, they changed according to the shape of beakers in which they are placed. Gases do not have a fixed shape or volume.

The spaces between the particles of gas are more so they can mix into each other very easily. 

Fluids are the substances that can flow easily so gas and liquid are the states which flow easily.

The forces of attraction are strongest in solids, followed by liquids and the weakest in gases.oxygen is a gas, water is a liquid and sugar is a crystalline solid.