preferred_name: n sulfur + H2 <=> (n-1) sulfur + hydrogen sulfide + H(+)
preferred_name_lc: n sulfur + h2 <=> (n-1) sulfur + hydrogen sulfide + h(+)
label: n sulfur + H2 <=> (n-1) sulfur + hydrogen sulfide + H(+)
label_lc: n sulfur + h2 <=> (n-1) sulfur + hydrogen sulfide + h(+)