Questions

The temperature at which water boils depends mainly on air pressure.

Thermoplastic materials is a type of plastic material that can be cooled and heated several times without any change in their chemistry or mechanical properties.

Examples of Thermoplastic ::

• polyethylene,
• polypropylene,
• polyvinyl chloride,
• polystyrene,
• polybenzimidazole,
• acrylic,
• nylon and
• teflon

Augustus was a Roman statesman and military leader who served as the first Emperor of the Roman Empire, controlling Imperial Rome from 27 BC until his death in AD 14. Jesus was born in 4 BC.

Hence, Augustus was the Roman Emperor when Jesus was born.

The marrow cavity is also known as the medullary cavity. It is the central cavity of bone shafts where adipose tissue is stored. It is lined with a thin, vascular membrane called endosteum.

Air pollutants are solid particles, gases, and liquid droplets in the air that can adversely affect ecosystems and the health of humans.

Major ambient air pollutants include toxic metals, polycyclic aromatic hydrocarbons, benzene, particulate matter (PM), nitrogen oxides, sulfur oxides, carbon monoxide, and ozone. Power plants, factories, and vehicle and air traffic are the most important anthropogenic sources of air pollution.

In addition, natural sources such as wildfires and volcanic activity contribute to ambient air pollution.

A redox reaction is a type of reaction which involves transfer of electrons among two species. This reaction is also called oxidation-reduction reaction.

In oxidation process, there is an increase in oxidation state of an atom, ion or molecule by losing the electrons.

In reduction process, there is a decrease in oxidation state of an atom, ion or molecule by accepting the electrons.

1)

In this reaction, Ba undergoes oxidation and Cl undergoes reduction.
This reaction is redox reaction.
In this reaction, oxidation number of Ba increases from 0 to +2 . So, Ba undergoes oxidation. The oxidation number of Cl decreases from 0 to -1. So, Cl undergoes reduction.

2) 

From this above reaction, it is clear that Aluminum undergoes oxidation and silver undergoes reduction.
Due to this, this reaction is redox reaction.

In this reaction, oxidation number of Aluminum increases from 0 to +1. So, aluminum undergoes oxidation. The oxidation number of silver decreases from +1 to 0. So, silver undergoes reduction.

3)

In this reaction, Mg undergoes oxidation and Br undergoes reduction.
This reaction is redox reaction.
The reactions 1, 3 and 4 are redox reactions.
In this reaction, oxidation number of Mg increases from 0 to +2 . So, Mg undergoes oxidation. The oxidation number of Br decreases from 0 to -1 . So, Br undergoes reduction.

Hence all the above reactions are redox reactions.