Which compound contains both covalent and ionic bonds kcl nh4cl mgcl2 ccl4

Explanation:

Before solving, let us understand the meaning of covalent and ionic bonds and how to identify them.

Ionic bonding is the complete transfer of valence electron(s) between atoms. It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.

A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms.

By definition, an ionic bond is between a metal and a nonmetal, and a covalent bond is between 2 nonmetals. So you usually just look at the periodic table and determine whether your compound is made of a metal/nonmetal or is just 2 nonmetals. The exception is a compound made with ammonium (NH4+)  Since ammonium is an ion, it forms ionic compounds.

So, now that we have got the basics covered, let us have a look at the options and apply what we just learnt;

A) KCl : K is a metal (belongs to group 1) and Cl is a non metal (group 7). The bond between them would be an ionic bond.

B) NH4Cl : NH4CL contains both an iconic and covalent bond. NH4Cl is made up of ammonium (NH4+) and Chlorine ion. The ammonium ion is polyatomic, which means it forms ionic salts. Therefore whatever bonds it makes are ionic. That said however, the bond between N and H is covalent because both N and H are non-metals. So NH4Cl contains both covalent and ionic bonds.

C) MgCl : Mg is a metal (belongs to group 2) and Cl is a non metal (group 7). The bond between them would be an ionic bond.

D) CCl4 : Since Carbon and Clhorine are non metals, the bond between them is a covalent bond.

describe matter a earth

the correct answer is:

a. formation of precipitation