At home, Helena is cooking with butter and lard. While the fats sit on the counter, she notices that the butter begins to melt, but the lard doesn't. Based on what she knows about fats, which product most likely contains the most hydrogen atoms

Lard contains the most hydrogen atoms

Explanation:

Unlike butter, lard contains more saturated fats, higher monounsaturated fats, and no trans fat (a type of unsaturated fat).

Thus, the presence of more saturated fats allows for more hydrogen atoms to confer heat stability to lard.

So, lard contains more hydrogen atoms