Yes, there are elements for which the atomic number (number of protons) is greater than their relative atomic mass (atomic weight). This can occur when an element has multiple isotopes, and the isotope with the highest natural abundance has a lower mass number compared to other isotopes.
Here are a few examples:
Hydrogen (atomic number 1, atomic weight 1.008): Hydrogen has three isotopes: protium (mass number 1), deuterium (mass number 2), and tritium (mass number 3). Protium is the most abundant isotope and has a mass number of 1, which is less than the atomic number.
Lithium (atomic number 3, atomic weight 6.94): Lithium has two isotopes: lithium-6 (mass number 6) and lithium-7 (mass number 7). However, lithium-7 is more abundant in nature, making the atomic weight of lithium greater than the mass number.
Boron (atomic number 5, atomic weight 10.81): Boron has two isotopes: boron-10 (mass number 10) and boron-11 (mass number 11). Boron-10 is the more abundant isotope, resulting in the atomic weight being less than the atomic number.
Nitrogen (atomic number 7, atomic weight 14.01): Nitrogen has two isotopes: nitrogen-14 (mass number 14) and nitrogen-15 (mass number 15). Nitrogen-14 is the more abundant isotope, causing the atomic weight to be less than the atomic number.
It's important to note that the atomic weight represents the weighted average of the naturally occurring isotopes of an element and can vary slightly depending on the isotopic composition of the element in different samples.