Answer:
The mass number is defined as the total number of protons and neutrons in an atom. The number of neutrons = mass number − atomic number.
The periodic table increases as you read left to right so it is A.
Answer:
None of the given options
Explanation:
Let's go case by case:
A. No matter the volume, the concentration of Fe(NO₃)₃ (and thus of [Fe³⁺] as well) is 0.050 M.
B. We can calculate the moles of Fe₂(SO₄)₃:
- 0.020 M * 0.80 L = 0.016 mol Fe₂(SO₄)₃
Given that there are two Fe⁺³ moles per Fe₂(SO₄)₃ mol, in the solution we have 0.032 moles of Fe⁺³. With that information in mind we <u>can calculate [Fe⁺³]</u>:
- 0.032 mol Fe⁺³ / 0.80 L = 0.040 M
C. Analog to case A., the molar concentration of Fe⁺³ is 0.040 M.
D. Similar to cases A and C., [Fe⁺³] = 0.010 M.
Thus none of the given options would have [Fe⁺³] = 0.020 M.
An increase in temperature increases the average kinetic energy of molecules.
When the temperature of a molecule increases, the molecule starts to move at a faster rate. The faster a molecule moves, the more kinetic energy it has.
