12
Neon is the 10th element and has 10 protons. The mass of an element is the sum of the protons and neutrons.
22-10=12
Answer:
The temperature to the nearest 0.5°C is 98.5°C
Answer:
0.34 moles
Explanation:
the molar mass of CaCl2 is 110.98g/mol
37.793 grams CaCl2 x 1 mole CaCl2/110.98grams = 0.34054mol CaCl2
Answer:
0.0986M is the concentration of the Na₂S₂O₃ solution
Explanation:
Potassium iodate, KIO₃, reacts with sodium thiosulfate, Na₂S₂O₃, as follows:
KIO₃ + 6Na₂S₂O₃ +5KI + 3H₂SO₄ → 3H₂O + 3K₂SO₄ + 3Na₂S₄O₆ + 6NaI
To solve this question we must find the moles of sodium thiosulfate that reacts as follows:
<em>Moles KIO₃:</em>
0.0250L * (0.0100mol / L) = 2.5x10⁻⁴moles KIO₃
<em>Moles Na₂S₂O₃:</em>
2.5x10⁻⁴moles KIO₃ * (6mol Na₂S₂O₃ / 1mol KIO₃) = 1.5x10⁻³ moles Na₂S₂O₃
<em>Molar concentration:</em>
1.5x10⁻³ moles Na₂S₂O₃ / 0.01521L =
<h3>0.0986M is the concentration of the Na₂S₂O₃ solution</h3>