Which of the following elements in Group 13 is a liquid at room temperature?
Boron
Aluminum
Gallium
Thallium
Gallium has a melting point of 29.8°C, which is lower than room temperature, so it is a liquid at room temperature. The other Group 13 elements are solids at room temperature.
Option (A) is incorrect because Boron is a solid at room temperature.
Option (B) is incorrect because Aluminum is a solid at room temperature.
Option(D) is incorrect because Thallium is a solid at room temperature.