The answer should be A, has more energy than it does in the ground state. De-excitation is removing electrons, so excitation would be adding more in to make it more stable. The ground state is what is considerd stable.
ANSWER: A
Answer:
4.8 %
Explanation:
We are asked the concentration in % by mass, given the molarity of the solution and its density.
0.8 molar solution means that we have 0.80 moles of acetic acid in 1 liter of solution. If we convert the moles of acetic acid to grams, and the 1 liter solution to grams, since we are given the density of solution, we will have the values necessary to calculate the % by mass:
MW acetic acid = 60.0 g/mol
mass acetic acid (the solute) = 0.80 mol x 60 g / mol = 48.00 g
mass of solution = 1000 cm³ x 1.010 g/ cm³ (1l= 1000 cm³)
= 1010 g
% (by mass) = 48.00 g/ 1010 g x 100 = 4.8 %
B. <span>The heat lost by the metal will equal the heat gained by the water</span>
Answer:
The answer to your question is 63.62 g/mol
Explanation:
Data
Copper-63 abundance = 69.17 %
Copper-65 abundance = 30.83 %
Average atomic mass = ?
Formula
Average atomic mass = [Atomic mass of Copper-63 x abundance] +
[Atomic mass of Copper-65 x abundance]
-Substitution
Average atomic mass = [63 x 69.17/100] + [65 x 30.83/100]
-Simplification
Average atomic mass = 43.58 + 20.04
-Result
Average atomic mass = 63.62 g/mol