Claim: Hans Heinrich Landolt was a Swiss chemist known for discovering iodine clock reaction and he attended the lectures of Carl Jacob Löwig (a German chemist who discovered bromine).
Evidence: Hans Heinrich Landolt (5 December 1831 – 15 March 1910) was a Swiss chemist who discovered iodine clock reaction. He attended the lectures of Carl Jacob Löwig and published his first work on stibmethyl in Schriften der Naturforschenden Gesellschaft (Writings of the Natural Science Society). Carl Jacob Löwig (17 March 1803 – 27 March 1890) was a German chemist and discovered bromine independently of Antoine Jérôme Balard. 
Carl Jacob Löwig (17 March 1803 – 27 March 1890) was a German chemist and discovered bromine independently of Antoine Jérôme Balard. Swiss Discovery of iodine clock reaction. Experimentally verified the law of conservation of mass and energy. Chemistry He attended the lectures of Carl Jacob Löwig and published his first work on stibmethyl in Schriften der Naturforschenden Gesellschaft (Writings of the Natural Science Society).