Which metal is a liquid at room temperature?

Mercury is the only non radioactive liquid metal at room temperature

Mercury, often referred to as quicksilver, is the only metal that exists in liquid form at room temperature. It remains liquid due to its unique atomic structure and weak metallic bonding, which prevents it from solidifying easily. Unlike most metals, which are solid at room temperature, mercury has a low melting point of about -38.83°C (-37.89°F), allowing it to remain liquid under standard conditions.

What makes mercury even more remarkable is that it is non-radioactive. While many elements and isotopes can exhibit radioactivity, mercury itself does not undergo radioactive decay under normal conditions. Its stable isotopes, particularly mercury-202, contribute to its non-radioactive nature. This makes it unique compared to other metals that may be found in liquid form, like gallium or cesium, which either require higher temperatures to remain liquid or may be radioactive.

Mercury's properties make it useful in a variety of applications, such as thermometers, barometers, and in certain electrical devices. However, due to its toxicity, mercury handling requires great care. Despite its benefits, it poses environmental and health risks, and therefore its use is increasingly regulated.