Explanation:
The melting point of a substance is the temperature at which it changes state from solid to liquid. Generally, elements with low melting point (room temperature) would tend to be in the liquid state of matter.
The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid. Generally, elements with high boiling point would tend to be in the liquid or solid state of matter.
Elements that satisfies both conditions above are liquid at room temperature.
There are two elements that are liquid in room temperature.
Bromine (Br) melts at 265.9 K and boils at 331.9K
Mercury (Hg) melts at 234.32 K and boils at 629.7K
There are four elements that melts slightly above the room temperature.
Francium (Fr) melts at 300 K
Cesium (Cs) melts at 301.59 K (fun fact - Cesium has the largest atoms. Cs atoms are about 30pm larger than Rubidium atoms)
Gallium (Ga) melts at 303.3 K
Rubidium (Rb) melts at 312.46 K
