Which of the following is the best example of chemical energy being converted into thermal energy? a. hydrogen turning into helium inside the Sun, giving off heat energy

b. burning a candle in a room

c. splitting uranium in a nuclear weapon, giving off heat

d. heating a molecule up so it can create a new substance

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.