A particular element has the following set of properties:

It has a low melting point.
It has a low boiling point
It exists as a two-atom molecule in the gas phase.
It has seven outer electrons.
It readily reacts with metals to produce a salt.

Which element does the list describe?

A.
bromine (Br)
B.
strontium (Sr)
C.
potassium (K)
D.
krypton (Kr)

Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas. Its properties are thus intermediate between those of chlorine and iodine. ... The colour fades at low temperatures, so that solid bromine at −195 °C

Explanation:

the answer would be a

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"