Which element has a reddish color in a gas and liquid state?

bromine.

Bromine is described as a red or red - brown or reddish - brown element and you can find some pictures in textbooks or internet that reflect this color, both as a gas and as a liquid.

When mixed with some organic clear solvents it produces a beautifull red mixture.

B.) falsehope this !

Rate law for this reaction israte of the reaction = k[a]²[b].second order in a  means concentration of a in power of two, and  first order in b means concentration of b in power of one.