Which list below contains only ionic compounds? A. CaCl2, H2O, LIF
B. CO2, K20, P4010
C. LiF, CaCl2, Mgo
D. NO2, Mgo, CuCl2

C. LiF, CaCl2, MgO

Explanation:

Ionic compound: It is that compound which consist of negative and position ions and held together by electrostatic force of attraction.

The ionic compound is neutral.

The ionic compound formed between metal and non-metal.

Covalent compound: It is that compound in which sharing of electrons between two atoms occur.

A.

H2O is not ionic compound. It is polar covalent.

Therefore, it does not contain only ionic compounds.

B.CO2,K2O,P4O10

CO2 and P4O10 are not ionic .It is covalent.

Therefore, it does not contain only ionic compounds.

C. LiF,CaCl2 ,MgO

All compounds are ionic because in given compounds one ion is negative  and one is metal (positive).

Therefore, it contains only ionic compounds.

D.NO2,MgO,CuCl2

NO2 is not ionic.

Therefore, it does not contain only ionic compounds.

Option C is correct.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west