5. is b
but im not sure about 4
hope this helps
Answer:
The answer to your question is Selenium
Explanation:
The origin of the names of the elements comes from different origins
For example
Sanskrit words. 14 elements have roots from this language
Planets, 4 elements took their names from the planets.
Greek, 42 elements took their names from these languages
The name of Selenium comes from the greek that means moon.
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical equation for reaction of potassium superoxide with carbon dioxide to produce oxygen and potassium carbonate will be:

Answer:
These reactions are similar because the process is similar and the products are carbon dioxide they are different because the substances are different to outgo these reactions
Explanation:
Answer:
Nice and you
Explanation:
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