What category of elements does krypton gas belong to?
a. metals
b. metalloids
c. non-metals

The correct answer is C. Non-metals

Explanation:

Krypton is one of the 118 chemical elements that have been identified. Krypton's main characteristics include lack of odor, color, and low reactivity, due to this, this element is classified as a noble gas and in the periodic table is part of the Group 18. Moreover, Krypton is part of the non-metals category that includes elements with low density, melting/boiling point, and conductivity, which are all features exhibit by Krypton as this has low electricity and heat conductivity, low density, low melting point (around -157 °C) and low boiling point (-153 °C). Thus, the category Krypton gas and in general Krypton belongs to is non-metals.