Answer:
the wavelength of radiation emitted is 
Explanation:
The energy of the Bohr's hydrogen atom can be expressed with the formula:

For n = 7:


For n = 4


The electron goes from the n = 7 to the n = 4, then :


Wavelength of the radiation emitted:

where;
hc = 1242 eV.nm


The two atoms shown in the equation are CALCIUM and oxygen.
<span>You start off with a neutral calcium atom with a shell of two electrons, a shell of 8 around that, a shell of 8 around that, and a shell containing 2...with no charge. </span>
<span>20 protons + 20 electrons. </span>
<span>You also have an oxygen atom with a shell of 2, and a shell of 6...with no charge. </span>
<span>8 protons + 8 electrons. </span>
<span>Each ionizes to form a calcium ion with 2 electrons removed (from the outer shell), leaving a +2 charge (20 protons, 18 electrons)... </span>
<span>and an oxygen ion with 2 electrons added (to the outer shell), leaving a -2 charge (8 protons, 10 electrons). </span>
<span>Their electrostatic attraction causes them to come together to form an ionic compound of CaO in a crystal lattice.</span>
Answer:
See explanation
Explanation:
When the complex ion Co(H2O)6 2+(aq) is placed in solution and chloride ions are added, the following equilobrium is set up;
Co(H2O)62+(aq) + 4 Cl-(aq) <=> CoCl42-(aq) + 6 H2O(g)
Co(H2O)6 2+(aq) solution is pink in colour while CoCl42-(aq) solution is blue in colour.
Since the solubility of CoCl42-(aq) is endothermic, heating the solution will move the equilibrium position towards the right (more CoCl42-(aq) is formed and the solution is blue in colour).
When the solution is cooled, more Co(H2O)62+(aq) is formed and the equilibrium position shifts towards the left and the solution becomes pink in colour.
Answer: Atoms of carbon and hydrogen
Explanation: