Answer:
Na(OH)²
Explanation:
We look for the charges in the periodic table
The periodic table is arranged by the outermost electrons of the elements and this is the statement among the given statements that explains how the periodic table is arranged. The correct option among all the options that are given in the question is the second option or option "B".
Organic molecules<span> are the </span>molecules<span> of life and are built around chains of carbon atoms that are often quite long. There are four main groups of </span>organic molecules<span>that combine to build cells and their parts: carbohydrates, proteins, lipids, and nucleic acids.</span><span>What is the basic of an organic molecule
</span>
Answer : The change in boiling point is, 
Explanation :
Formula used :
where,
= change in boiling point = ?
i = Van't Hoff factor = 3 (for MgI₂ electrolyte)
= boiling point constant for water = 
m = molality = 0.615 m
Now put all the given values in this formula, we get
Therefore, the change in boiling point is,
The number of half -lives that has passed after 105 hours for krypton-79 that has half-life of 35 hours is calculated as below
if 1 half life = 35 hours
what about 105 hours = ? half-lives
= (1 half life x105 hours) /35 hours = 3 half-lives has passed after 105 hours
