Answer
7.1 g is the mass of chlorine that entered in chemical reaction.
Work Step by Step
1- Apply the law of conservation of mass for this chemical reaction:
m (of sodium bromine) + m (chlorine) = m (of bromine) + m (of sodium chlorine)
2- Replace the mass of sodium bromine, mass of bromine and mass of sodium chlorine, in order to find the mass of chlorine that have entered the reaction:
20.6 g + m (of chlorine) = 16.0 g + 11.7 g
20.6 g + m (of chlorine) = 27.7 g
m (of chlorine) = 27.7g – 20.6 g
m (of chlorine) = 7.1 g
Therefore the mass of chlorine that entered in chemical reaction was 7.1 g.