Carbon-13 has 7 neutrons and carbon-12 has 6 neutrons. Carbon-12 is the most common isotope of carbon. Carbon-14 is radioactive and very rare. The symbols for the isotopes of carbon atoms shown here indicate they each have six protons but mass numbers of 14, 13 and 12.
The reaction is as follows:
2 H₂(g) + O₂(g) → 2 H₂O(g) . ΔH = - 483.5 kJ
Using the change in enthalpy and heat, calculate the moles as follows:
Moles of H₂ = -

x 2 mol H₂
= - 216 kJ / (-483.5 kJ) x 2 mol H₂
= 0.893 mol H₂
Calculate the mass of H₂ using the moles and molar mass as follows:
0.893 mol H₂ x (2.02 g H₂ / 1 mol H₂) = 1.79 g H₂
Therefore, the mass of hydrogen gas is 1.79 g
I did the math and i got 450 but i dont know if its right
<h3>Answer: sorry i don't know what the answer that question </h3>