Why is NCl3 not soluble in water?

Explanation:

NCl3 does not dissolve in water because it is a nonpolar molecule which is different with water. NCl3 is nonpolar due to the difference in electronegativities between 3 atoms of Cl and 1 atom if N2.

A polar solute dissolves into a polar solvent and a non-polar compound dissolves into a non-polar solvent, this rule is known as "like dissolves like".

d: the voltage of the secondary coil is less than that of the primary coil.

im not suree sorry if wrong

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.