They have a magnetic attraction.
They have seven electrons in their valence shell, so halogens are very reactive.
Hope this helps! :)
The answer is - ide.
That is how you name the anions in a ionic compound, you replace the ending of the name of the element with ide.
Some examples:
Ionic compound anion name of the anion
NaCl Cl- chloride
KF F- fluoride
NaI I- iodide
CaBr2 Br- bromide
Answer: There are 0.499 moles present in
molecules of Boron trichloride.
Explanation:
According to mole concept, there are
molecules present in 1 mole of a substance.
Hence, number of moles present in
molecules are as follows.

Thus, we can conclude that there are 0.499 moles present in
molecules of Boron trichloride.