A student heats up solid X. it starts to melt at 35°c, and finishes melting at 40°C. what does this tell you about solid X. a. solid X is a pure compound
b. solid X is a pure element
c. solid X is an impure substance
d. solid X is an impure compound​

i think that the answer is c

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.

pv=nrt

explanation: