the mass number of fluorine (F) is 19
C. 19
Answer:
1 and 3
Explanation:
The vertical columns (groups) of the periodic table are arranged such that all its elements have the same number of valence electrons. All elements within a certain group thus share similar properties.
Answer:
See explanation
Explanation:
The balanced redox reaction equation is;
8H+ + MnO4^- + 5Fe2+ ---------> Mn2+ + 5Fe3+ + 4H2O
Amount of KMnO4 reacted = 31.60/1000 * 0.05120 = 1.62 * 10^-3 moles
From the reaction equation;
1 mole of MnO4^- reacted with 5 moles of Fe2+
1.62 * 10^-3 moles will react with 1.62 * 10^-3 moles * 5/1 = 8.1 * 10^-3 moles
Mass of Fe2+ reacted = 8.1 * 10^-3 moles * 56 g/mol
Mass of Fe2+ reacted = 0.45 g
Amount of iron in the sample = 0.45 g
Percentage of iron in the sample;
0.45 g/4.230 g * 100 = 10.6 %
Answer:
It’s true
Explanation:
If we account for all reactants and products in a chemical reaction, the total mass will be the same at any point in time in any closed system. ... The Law of Conservation of Mass holds true because naturally occurring elements are very stable at the conditions found on the surface of the Earth.