Answer:
c. -1020.9 kJ
Explanation:
4Fe (s) + 3 O₂ (g) --> 2 Fe₂O₃(s) ΔH = -826.0 kJ/mol.
atomic weight of iron = 56
69.03 g = 69.03 / 56
= 1.23268 moles
Heat released by 1.23268 moles
= 1.23268 x 826.0
= -1020.9 kJ .
A solid, a liquid or a gas.
The mass fraction of sodium chloride is 0.0625
<h3>What is the mass fraction of sodium chloride in the solution?</h3>
The mass fraction of sodium chloride is the ratio of the mass of sodium chloride to the total mass of the solution.
The mass fraction of sodium chloride is determined as follows;
mass of sodium chloride = 20 g
- mass of water = volume * density
density of water = 1 g/mL
volume of water = 300 mL
mass of water = 300 mL * 1 g/mL
mass of water = 300 g
total mass of solution = 20 + 300 = 320 g
mass fraction of sodium chloride = 20/320
mass fraction of sodium chloride = 0.0625
Learn more about mass fraction at: brainly.com/question/14783710
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Ionic compounds generally occur between metals and non-metals due to their large electronegativity difference. You can simple go down Group 1 and Group 17 of the periodic table.
Examples:
NaCl (Sodium Chloride)
KCl (Potassium Chloride)
RbCl (Rubidium Chloride)
CsCl (Cesium Chloride)
Answer:
Since electrons cannot have the same set of quantum numbers, a maximum of two can be in the n = 1 level, and a third electron must reside in the higher-energy n = 2 level. If there are two electrons in the n = 1 level, their spins must be in opposite directions.
