2H₂ + O₂ = 2H₂O
n(H₂)=m(H₂)/M(H₂)
n(H₂)=5g/2.0g/mol=2.5 mol
n(O₂)=m(O₂)/M(O₂)
n(O₂)=40g/32.0g/mol=1.25 mol
H₂ : O₂ = 2 : 1
2.5 : 1.25 = 2 : 1
n(H₂O)=n(H₂)=2n(O₂)=2.5 mol
m(H₂O)=n(H₂O)M(H₂O)
m(H₂O)=2.5mol*18.0g/mol=45.0 g
Answer:
4770 grams of sodium carbonate
Explanation:
The reaction that takes place between sodium carbonate and sulfuric acid is:
- Na₂CO₃ (s) + H₂SO₄ (aq) → Na₂SO₄ (aq) + CO₂(g) + H₂O (l)
First we <u>calculate how many H₂SO₄ moles reacted</u>, using the <em>given concentration and volume of solution</em>:
moles = Molarity * Liters
- moles = 18.0 M * 2.50 L = 45 mol H₂SO₄
Then we <u>convert H₂SO₄ moles into NaCO₂ moles</u>, using the <em>stoichiometric coefficients</em>:
- 45 mol H₂SO₄ * = 45 mol NaCO₂
Finally we <u>convert 45 NaCO₂ moles into grams</u>, using its <em>molar mass</em>:
- 45 mol NaCO₂ * 106 g/mol = 4770 g
Process energy required
1) raise the temperature to 75.0 °C 628 J
2) evaporate the liquid at 75.0°C 15.6 KJ = 15,600 J
3) raise the temperature to ? 712 J
Total energy: 628 J + 15,600 J + 712 J = 16,940 J
As you must have realized the clue to do the problem correctly is to convert all the energy values to joules, because you cant not add up joules with kilo joules.
Answer: 16,940 J
An element is composed of a single type of cell. So we can expect only one kind of element. For example if it is a carbon element it will contain only carbon atoms.
Atomic radius decreases and electronegativity
increases in order of increasing atomic number
good luck