金屬的液體

金屬的熔點通常都很高，在常溫（25oC）常壓（1 atm）下通常都呈固態，但也有例外。

在常溫常壓下，汞（英文名稱 Mercury、化學符號 Hg、俗稱水銀）是唯一的液態金屬，它的熔點是 -38.83oC。

另有少數的金屬的熔點較低，接近常溫。例如鎵（英文名稱 Gallium、化學符號 Ga）的熔點是 29.76oC，可以用手掌的熱力把鎵由固體變成液體。

In answer 002, the sentence "However, at temperatures between 25 C~ 40 C, four metal elements are in liquid state. " is INCORRECT.

It should be:
"However, there are four metals having melting point between 25 C to 40 C."

At standard room temperature, mercury (melting point = -39 C) is the only metal that is in liquid state.
However, at temperatures between 25 C~ 40 C, four metal elements are in liquid state. They are Francium, gallium, caesium and rubidium. The melting points of which are respectively, 27 C, 30 C, 29 C and 39 C.
Please refer to the following web-page for details:
http://chemistry.about.com/od/periodictableelements/a/liquidelements.htm