Question

Which element among Al, Au, Br, Ca, Cs, F, H, He, Hg, I, K, Mg, Na, O, P, S, and Si is gaseous at room temperature?

a) H
b) He
c) F
d) O

Answer 1

b) He.The element from the given list that is gaseous at room temperature is He (helium), a noble gas that is non-reactive and exists as a gas under normal conditions.

Step-by-step explanation:

The element among Al, Au, Br, Ca, Cs, F, H, He, Hg, I, K, Mg, Na, O, P, S, and Si that is gaseous at room temperature is He (helium). Helium is one of the noble gases, which are known for their lack of reactivity and for existing in the gas state under normal conditions of temperature and pressure.

The other options given are either solid or liquid at room temperature or, in the case of F (fluorine) and O (oxygen), are gases but are not provided as options in the multiple-choice question listed