The answer is 64.907 amu.
The atomic mass of an element is the average of the atomic masses of its isotopes. The relative abundance of isotopes must be taken into consideration, therefore:
atomic mass of copper = atomic mass of isotope 1 * abundance 1 + atomic mass of isotope 2 * abundance 2
We know:
atomic mass of copper = 63.546 amu
The atomic mass of isotope 1 is: 62.939 amu
The abundance of isotope 1 is: 69.17% = 0.6917
The atomic mass of isotope 1 is: x
The abundance of isotope 2: 100% - 69.17% = 30.83% = 0.3083
Thus:
63.546 amu = 62.939 amu * 0.6917 + x * 0.3083
63.546 <span>amu = 43.535 amu + 0.3083x
</span>⇒ 63.546 amu - 43.535 amu = 0.3083x
⇒ 20.011 amu = 0.3083x
⇒ x = 20.011 amu ÷ 0.3083 = 64.907 amu
The molarity of a solution that contains 20.0grams of sodium hydroxide in 200. ml of solution is 2.3 M.
<h3>What is Molarity? </h3>
Molarity is defined as the ratio of number of moles of solute to the volume of the solution.
Molarity = number of moles of solute/ Volume of solution
Given,
given mass of sodium hydroxide= 20 g
Volume of the solution = 200 mL.
Firstly, we will calculate the moles of sodium hydroxide.
<h3>What is Mole? </h3>
Mole is defined as the ratio of given mass of substance to the molar mass of substance.
Mole = given mass/ molar mass
Molar mass of sodium hydroxide = 40 g
Mole = 20/40
= 0.5 mol
Molarity = (0.5/ 200) × 1000 = 2.5M
Thus, we calculated that the molarity of a solution that contains 20.0grams of sodium hydroxide in 200. ml of solution is 2.3 M.
learn more about Molarity:
brainly.com/question/19517011
#SPJ4
Answer:
The process of the first ionization energy
Explanation:
The ionization energy is the energy required to remove one electron for one isolated atom at the gas phase. The first electron to be removed is the valence electron which is far away from the nuclei. Because of that, this electron suffers a less attraction force.
For the second ionization energy, the electron will be closer to the nuclei, so it is more attracted, then a large amount of energy is necessary to remove it. For the third, the amount of energy will be larger. So, the first ionization energy requires the least amount of energy.
Diamond is not a rock it is a mineral.
