Video Transcript
Which of the following reactions is
unlikely to produce a salt? (A) Zn plus H2SO4. (B) Two NH3 plus two O2. (C) HCl plus NaOH. (D) Na2CO3 plus two HCl. Or (E) CuO plus H2SO4.
A salt is an ionic compound made of
cations and anions. Cations are positively charged ions
and are typically formed by metals, which can be found on the periodic table to the
left of the dotted zigzag line. A cation can be formed by losing
electrons. For example, the metal sodium, when
forming ionic compounds, often loses one valence electron, thus taking on a charge
of one plus. Anions are negatively charged ions
and are often formed by nonmetals, which can be found to the right of the dotted
zigzag line on the periodic table. Anions can be formed by an atom
gaining electrons. For example, the nonmetal chlorine,
when forming ionic compounds, often gains one valence electron taking on a one-minus
charge.
Cations and anions combine to form
a salt. Because salts have both a positive
cation component and a negative anion component, this will generally result in the
salt having a neutral charge overall, although there are some exceptions.
Let’s look at our answer
choices. There is only one answer choice
that does not have both metals and nonmetals present, which is answer choice
(B). This reaction will not form a salt
but instead forms a nitrogen oxide and water, neither of which are ionic
substances. Even though hydrogen is on the left
side of the periodic table, it is to the right of the dotted zigzag line and thus is
a nonmetal. So it tends to behave covalently
rather than ionically.
The reaction between ammonia and
oxygen is unlikely to form a salt, so the correct answer is (B) two NH3 plus two
O2.
