Below are two different chemical formulas.

Question

Formula 1: CaCl2

Formula 2: CaC2


Which statements about the chemical symbols of the elements within each formula are correct? Select two.
A.
Both formulas contain one atom of the element aluminum.
B.
Both formulas contain one atom of the element calcium.
C.
Formula 2 contains two atoms of the element carbon.
D.
Both formulas contain the element carbon.
E.
The second formula contains three atoms of the element carbon.

Answer 1

To analyze the formulas:

• Formula 1: CaCl2

  • Contains:
    • 1 atom of Calcium (Ca)
    • 2 atoms of Chlorine (Cl)

• Formula 2: CaC2

  • Contains:
    • 1 atom of Calcium (Ca)
    • 2 atoms of Carbon (C)

Now, let's evaluate the statements:

A. Both formulas contain one atom of the element aluminum.

• Incorrect. Neither formula contains aluminum.

B. Both formulas contain one atom of the element calcium.

• Correct. Both formulas contain 1 atom of calcium.

C. Formula 2 contains two atoms of the element carbon.

• Correct. Formula 2 (CaC2) contains 2 atoms of carbon.

D. Both formulas contain the element carbon.

• Incorrect. Formula 1 (CaCl2) does not contain carbon.

E. The second formula contains three atoms of the element carbon.

• Incorrect. Formula 2 (CaC2) contains only 2 atoms of carbon.

The two correct statements are:

• B. Both formulas contain one atom of the element calcium.
• C. Formula 2 contains two atoms of the element carbon.