According to Dalton; All matter is made up of small particles called atoms.
Answer:
The main difference between the two models was about the location of the electron in an atom.
Explanation:
<u>Rutherford described that:</u>
- The electrons were outside of the nucleus.
- They were equal in number to the "positiveness" of the nucleus.
- Also, He randomly placed the negative electrons outside the nucleus.
<u>Bohr improved the Rutherford model:</u>
- Bohr placed the electrons in distinct energy levels.
- Electrons only exist in fixed orbitals (shells) and not anywhere in between.
- Each shell has a fixed energy
- Rutherford explained the nucleus of an atom, while Bohr was more into the electrons and their energy levels.
Seems correct. Your steps make sense, the molar ratios are right and you've done it in a clear easy to follow manner. I see no issues with it.
Answer:
0.067 M
Explanation:
Given data:
Volume of solution = 1.00 L
Mass of BaCl₂ = 14 g
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Now we will calculate the number of moles first.
Number of moles = mass/ molar mass
Number of moles = 14 g/ 208.23 g/mol
Number of moles = 0.067 mol
Now we will calculate the molarity.
Molarity = 0.067 mol / 1.00 L
Molarity = 0.067 M ( mol/L=M)
Answer:
3.89002 × 10 ⁻⁷m = 389.002nm.
Explanation:
Without mincing words let's dive straight into the solution to the problem above. To calculate the wavelength of the line in the absorption line spectrum of hydrogen caused by the transition of the electron from an orbital with n = 2 to an orbital with n = 8, there is the need to make use of the change in energy equation.
The change in energy = 2.18 × 10⁻¹⁸ [ 1/2² - 1/8²] = 2.18 × 10⁻¹⁸ × [0.25 - 0.015625] = 2.18 × 10⁻¹⁸ × 0.234375 = 5.11 × 10⁻¹⁹.
Therefore, the wavelength = plank's constant × speed of light/ change in energy = 6.626× 10⁻³⁴ × 3 × 10⁸/ 5.11 × 10⁻¹⁹ = 1.9878 × 10⁻²⁵/ 5.11 × 10⁻¹⁹ = 0.389002 × 10⁻⁶ = 3.89002 × 10 ⁻⁷m = 389.002nm.