Answer:
B.Lone pair in pyrrolidine ring is localized and, therefore, is expected to be more reactive.
Explanation:
There are two nitrogen atoms bearing lone pairs of electrons in the structure of nicotine as shown in the image attached.
One nitrogen atom is found in the pyrrolidine ring. The lone pair on this nitrogen atom is localized hence it is more reactive than the lone pair of electrons found on the nitrogen atom in the pyridine ring which is delocalized a shown in the image attached to this answer.
FILTRATION When the substances in a mixture have different particle sizes, they are separated by filtration. The mixture is poured through a sieve or filter. The smaller particles slip through the holes, but the larger particles do not.p
Answer:

Explanation:
Here, we want to calculate the number of formula units in the given molecule
We start by getting the number of moles
To get the number of moles, we have to divide the mass given by the molar mass
The molar mass is the mass per mole
The molar mass of calcium bromide is 200 g/mol
Thus, we have the number of moles as follows:

The number of formula units in a mole is:

The number of formula units in 0.2075 mole will be:
Hello!
Elements are made up of atoms, and elements combine to make compounds. Compounds are made up of molecules, and molecules are made up of atoms.
Nitrogen is an element. It could be made up of one or many atoms. A mixture is made up of compounds, so it is not the answer.
Molecules and compounds are made up of different atoms and elements, but nitrogen is not a molecule or a compound.
There is such a thing as a nitrogen atom, though.
Therefore, your answer would be 2) Atom.
I hope this helps!