By 1920, physicists knew that most of the mass of the atom was located in a nucleus at its center, and that this central core contained protons. In May 1932 James Chadwick announced that the core also contained a new uncharged particle, which he called the neutron
Which atom?
Atomic mass - proton
Answer:
This lifespan began roughly 4.6 billion years ago, and will continue for about another 4.5 – 5.5 billion years, when it will deplete its supply of hydrogen, helium, and collapse into a white dwarf.
Explanation:
Got this from the internet lol
Answer:
11.92 g ≅ 12.0 g.
Explanation:
- The balanced equation of the reaction is: CO + 2H₂ → CH₃OH.
- The stichiometry shows that 1.0 mole of CO reacts with 2.0 moles of H₂ to produce 1.0 mole of CH₃OH.
- Now, we need to calculate the no. of moles (n) of the reacted CO and H₂ using the relation: <em>n = mass / molar mass.</em>
- No. of moles of CO = mass / molar mass = (14.0 g) / (28.01 g/mol) = 0.4999 mol ≅ 0.5 mol.
- No. of moles of H₂ = mass / molar mass = (1.5 g) / (2.015 g/mol) = 0.7444 mol.
- As showed in the balanced equation: every 1.0 mole of CO needs 2.0 moles of hydrogen to react completely.
- So, for the given data H₂ gas (0.7444 mol) will be the limiting reactant that reacts completely with (0.372 mol) of CO which is in excess (0.5 mol).
- We can get the no. of moles of CH₃OH produced.
<u><em>Using cross multiplication:</em></u>
2 moles of H₂ produce → 1.0 mole of CH₃OH, from the stichiometry.
0.7444 moles of H₂ produce → ??? mole of CH₃OH.
- The no. of moles of CH₃OH produced = (0.7444 moles)(1.0 mole) / (2 moles) = 0.372 mol.
- The amount of CH₃OH produced in grams (mass) = n x molar mass = (0.372 mol) (32.04 g/mol) = 11.92 g ≅ 12.0 g.