The balanced chemical equation for the reaction of hydrogen and oxygen is shown below. 2H2 + O2 → 2H2O
The number of moles of hydrogen that is needed to produce 0.253 mol of water is
O smaller than 0.253 mol.
O much greater than 0.253 mol.
O slightly greater than 0.253 mol.
O equal to 0.253 mol.

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.  

qualitative observation deals with data that can be observed with our senses: sight, smell, touch, taste, and hearing. they do not involve measurements or numbers. for instance, colors, shapes, and textures of objects are all qualitative observations.