Acids are defined as substances that donate protons (H+) when dissolved in water. While hydrogen is always present in acids, oxygen is not always a component.

Therefore, the class of elements found in acids besides hydrogen depends on the specific acid:

* Non-metal elements: Many acids contain a non-metal element, such as chlorine (HCl - hydrochloric acid), sulfur (H2SO4 - sulfuric acid), or nitrogen (HNO3 - nitric acid).

* Organic acids: These acids contain carbon and often other elements like oxygen, hydrogen, and nitrogen. For example, acetic acid (CH3COOH) is a common organic acid found in vinegar.

* Binary acids: These acids consist of only two elements, hydrogen and a non-metal. For example, hydrogen fluoride (HF) is a binary acid.

In summary, acids contain hydrogen, but the other element(s) can vary depending on the specific acid.