Question

about 99% of earths atmosphere consists of n₂ (nitrogen molecules) and o₂ (oxygen molecules); there are also small amounts of ar (the atom argon) and co₂ (carbon dioxide). the two nitrogen atoms in n₂ are triple - bonded to each other; the two oxygen atoms in o₂ are double - bonded to each other; both os in co₂ are double - bonded to the c. the co₂ molecule is linear, not bent.
hint: before you answer the questions below, diagram the atoms and bonds in each of the three molecules (n₂, o₂, and co₂) and indicate the positions of the bonded electrons and any full or partial charges.
which of the following statements are true? select all that apply.
□ there is no difference in how well o₂ and n₂ dissolve, and both dissolve poorly in water.
□ like all atoms, ar has no charge or partial charge so dissolves poorly in water.
□ o₂ dissolves in water better than n₂, because oxygen atoms are more electronegative than n atoms.
□ because co₂ is not bent, the overall molecule is not polar.
□ co₂ can hydrogen bond with water due to the partial charges on each o, so the molecule dissolves moderately well.
□ n₂ dissolves in water better than o₂, because the triple bonds between nitrogen atoms make the molecule extremely stable.

Explanation:

1. Both $O_2$ and $N_2$ are non - polar molecules and dissolve poorly in water, a polar solvent. So, the statement "There is no difference in how well $O_2$ and $N_2$ dissolve, and both dissolve poorly in water" is true.
2. Argon (Ar) is a noble gas atom. It is non - polar and has no charge or partial charge, so it dissolves poorly in water, a polar solvent. The statement "Like all atoms, Ar has no charge or partial charge so dissolves poorly in water" is true.
3. While oxygen is more electronegative than nitrogen, both $O_2$ and $N_2$ are non - polar and their solubility in water is mainly due to their non - polarity rather than electronegativity differences, so $O_2$ does not dissolve better in water than $N_2$ because of electronegativity. This statement is false.
4. $CO_2$ is a linear molecule. The bond dipoles from the C - O bonds cancel out due to the linear geometry, making the overall molecule non - polar. The statement "Because $CO_2$ is not bent, the overall molecule is not polar" is true.
5. $CO_2$ cannot hydrogen bond with water directly. Hydrogen bonding requires a hydrogen atom bonded to a highly electronegative atom (N, O, F) in one molecule interacting with a highly electronegative atom in another molecule. $CO_2$ has no such hydrogen atoms directly bonded to O, N or F. So the statement " $CO_2$ can hydrogen bond with water due to the partial charges on each O, so the molecule dissolves moderately well" is false.
6. $N_2$ does not dissolve better in water than $O_2$. Their solubility is mainly determined by their non - polarity rather than the strength of the bonds within the molecule. So the statement " $N_2$ dissolves in water better than $O_2$, because the triple bonds between nitrogen atoms make the molecule extremely stable" is false.

Answer:

• There is no difference in how well $O_2$ and $N_2$ dissolve, and both dissolve poorly in water.
• Like all atoms, Ar has no charge or partial charge so dissolves poorly in water.
• Because $CO_2$ is not bent, the overall molecule is not polar.