Why does one mole of carbon atoms have a smaller mass than one mole of sulfur atoms?

Every mole of a substance weighs equal to the atomic mass of that substance. Atomic mass depends on the number of protons and number of neutrons.

Carbon is an element with atomic number of 6 and mass number of 12. Thus it has 6 protons and 6 neutrons.

Sulphur is an element with atomic number of 16 and mass number of 32. Thus it has 16 protons and 16 neutrons.

Carbon has an atomic mass of 12 whereas sulphur has an atomic mass of 32.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

the increase of protons   hope this