In which of the following pairs of compounds are both members of the pair ionic compounds? Explain
a. Pl3 and HBr
b. H2S and NCl3
c. LiF and H20
d. LiI and NiO
DrBob222 you said you would choose the answer d and I should know how to figure this out. I don't understand the pair ionic compounds. Can you please explain it to me in lay-man terms. I'm slooow
Thanks
Sure, I can explain it to you in simple terms.
Ionic compounds are formed when there is a transfer of electrons between atoms. One atom loses electrons to form a positively charged ion, known as a cation, and another atom gains those electrons to form a negatively charged ion, known as an anion. The oppositely charged ions are held together by strong electrostatic forces, creating an ionic bond.
In the pairs you provided:
a. Pl3 and HBr
- Pl3 is a covalent compound, not ionic, because phosphorus tends to form covalent bonds with other elements.
- HBr is also a covalent compound, not ionic, because hydrogen and bromine atoms tend to share electrons in covalent bonds.
b. H2S and NCl3
- H2S is a covalent compound, not ionic, because hydrogen and sulfur atoms form covalent bonds by sharing electrons.
- NCl3 is also a covalent compound, not ionic, because nitrogen and chlorine atoms share electrons to form covalent bonds.
c. LiF and H2O
- LiF is an ionic compound because lithium loses one electron to form a cation (Li+), and fluoride gains that electron to form an anion (F-). The attraction between Li+ and F- ions creates an ionic bond.
- H2O is a covalent compound because oxygen and hydrogen atoms share electrons to form covalent bonds.
d. LiI and NiO
- LiI is an ionic compound because lithium loses one electron to form a cation (Li+), and iodine gains that electron to form an anion (I-). The attraction between Li+ and I- ions creates an ionic bond.
- NiO is also an ionic compound because nickel loses electrons to form a cation (Ni2+), and oxygen gains those electrons to form an anion (O2-). The attraction between Ni2+ and O2- ions creates an ionic bond.
Therefore, in the pairs you provided, only LiI and NiO are both ionic compounds.
No problem, I'll be happy to explain it to you in simple terms.
Ionic compounds are formed when electrons are transferred from one element to another, resulting in the formation of ions. These ions, with opposite charges, are attracted to each other through electrostatic forces, forming a bond. Usually, one element will lose electrons and become positively charged (a cation), while the other element will gain electrons and become negatively charged (an anion).
To determine if a pair of compounds is ionic, we need to check if they consist of a metal cation and a nonmetal anion. In other words, one compound should contain a metal element, and the other compound should contain a nonmetal element.
Now, let's analyze the options you mentioned:
a. Pl3 and HBr:
Pl3 is not a recognized compound, but assuming you meant PCl3 (phosphorus trichloride), it consists of a nonmetal (phosphorus) and a nonmetal (chlorine). Therefore, it is not an ionic compound. HBr, on the other hand, consists of a nonmetal (hydrogen) and a nonmetal (bromine). So, neither Pl3 nor HBr are ionic compounds.
b. H2S and NCl3:
H2S consists of a nonmetal (hydrogen) and a nonmetal (sulfur), so it is not an ionic compound. NCl3 contains a nonmetal (nitrogen) and a nonmetal (chlorine), so it is also not an ionic compound.
c. LiF and H2O:
LiF consists of a metal (lithium) and a nonmetal (fluorine). Therefore, it is an ionic compound. H2O, also known as water, is composed of two nonmetals (hydrogen and oxygen). Hence, H2O is not an ionic compound.
d. LiI and NiO:
LiI contains a metal (lithium) and a nonmetal (iodine), making it an ionic compound. NiO consists of a metal (nickel) and a nonmetal (oxygen), so it is also an ionic compound.
Therefore, out of the provided options, only the pair LiI and NiO contains both members as ionic compounds.
The idea of predicting which is ionic, which covalent, which polar covalent depends upon some man made definitions and how to interpret them.
Look up the value for the electronegativity (EN) for each element. If the difference is about 1.9 or so it is about 50% covalent/50% ionic bond. Generally, if it is more than 1.9 we call it an ionic bond; if less than 1.9 we call it a covalent bond. This number of 1.9 varies with instructors so you should know what your prof uses.(I know some use 1.7.) Also, some profs like to point out that a difference of zero is a pure covalent bond(H2, O2, N2 are example) while values between zero and 1.9 are not strictly covalent but not ionic either so those are called polar covalent. To show the examples above, here are the EN values of some of them.
P = 2.19
I = 2.66
so PI3 is not ionic so I need not even worry about HBr; however, to show it is covalent too H = 2.1 and Br = 2.96 diff = <1
b. Both are covalent. You can go through the drill to confirm that.
c. Li is about 1; F is 4.0; difference is 3 so it clearly is ionic. H2O, however, is not. H = 2.1; O = about 3.5 for diff of about 1.4 or so. This is not ionic but it is polar covalent.
d. Li = about 1
I = about 2.66
diff = about 1.7
Ni = about 1.9
O = about 3.5
diff = about 1.4
Strictly speaking none of these meet the criteria of BOTH being ionic by the criteria I use. I looked at them and knew the answer couldn't be a,b,or c so I figures d without looking up the values. You need to take the above information, use the tables your prof is using as well as his/her definition of ionic/covalent bond (the difference of EN values) and re-evaluate each based on the values your prof used.
Note: If your prof uses 1.7 and the EN values in his/her table varies a little (Li = 1 and I = 2.7 diff = 1.7
Ni = 1.8 and 3.5 diff = 1.7
that would make d the answer.