Answer: 
Explanation:
A single displacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. Thus one element should be different from another element.
Synthesis reaction is defined as the reaction where substances combine in their elemental state to form a single compound.
Decomposition reaction is defined as the reaction where a single substance breaks down into two or more simpler substances.
Combustion is a type of chemical reaction in which hydrocarbons burn in the presence of oxygen to form carbon dioxide and water along with heat.
Part 1 :- Super gaint star have mass from 10 to 70 solar masses and brightness from 30,000 upto hundreds of thousand times the solar luminosity
blue super giant surface temperature is 20,000 to 50,000 degree Celsius example :0 Rigel its mass is around 20 times the sun mass it give light which 60,000 sun together give .
part 2 :- HR diagram : hertzsprung -Russel diagram ( attached below)
Atomic mass is the mass of a chemical element expressed in atomic mass units. Molar mass the mass of a given substance divided by its amount of substance in (mol) .
Answer:
number of ions = 12.04 x 10^²³
Explanation:
n = number of ions/Avogadro's constant
2 = number of ions/6.02 x 10^²³
number of ions= 2 x 6.02 x 10^²³
number of ions = 12.04 x 10^²³
