Gallium and casium have so low melting points that they melt even on keeping them on the palm.

Introduction:
At body temperature, which is typically around 37 degrees Celsius (98.6 degrees Fahrenheit), there are two metals that exist in a liquid state: Mercury (Hg) and Galinstan.

Mercury (Hg):
Mercury is a unique metal that remains in a liquid state at room temperature and does not solidify until it reaches -38.83 degrees Celsius (-37.89 degrees Fahrenheit). It is the only metal that is liquid at standard conditions for temperature and pressure. Mercury has a silvery appearance and is commonly used in thermometers, barometers, and electrical switches due to its unique properties, such as high density and low freezing point. However, it is important to note that mercury is highly toxic and poses serious health risks if mishandled or ingested.

Galinstan:
Galinstan is a eutectic alloy composed of gallium, indium, and tin, which remains in a liquid state at body temperature. It is often used as a safe alternative to mercury due to its non-toxic nature. Galinstan has a low melting point of -19 degrees Celsius (-2 degrees Fahrenheit) and remains liquid up to temperatures exceeding 130 degrees Celsius (266 degrees Fahrenheit). It has excellent thermal conductivity and is commonly used in applications such as thermometers, heat transfer systems, and medical devices.

Conclusion:
In conclusion, the only metals that exist in a liquid state at body temperature are mercury and galinstan. While mercury is a toxic element, galinstan provides a safer alternative with similar properties. These metals have various applications in fields such as instrumentation, electronics, and healthcare. It is important to handle mercury with caution due to its toxicity, and galinstan serves as a suitable substitute in many cases.