Answer:
Frequency = 3.16 ×10¹⁴ Hz
λ = 0.95×10² nm
Explanation:
Energy associated with nth state is,
En = -13.6/n²
For n = 1
E₁ = -13.6 / 1²
E₁ = -13.6/1
E₁ = -13.6 ev
Kinetic energy of electron = -E₁ = 13.6 ev
For n = 5
E₅ = -13.6 / 5²
E₅ = -13.6/25
E₅ = -0.544 ev
Kinetic energy of electron = -E₅ = 0.544 ev
Wavelength of radiation emitted:
E = hc/λ = E₅ - E₁
hc/λ = E₅ - E₁
by putting values,
6.63×10⁻³⁴Js × 3×10⁸m/s / λ = -0.544ev - (-13.6 ev )
6.63×10⁻³⁴ Js× 3×10⁸m/s / λ = 13.056 ev
λ = 6.63×10⁻³⁴ Js× 3×10⁸m/s /13.056 ev
λ = 6.63×10⁻³⁴ Js× 3×10⁸m/s /13.056 × 1.6×10⁻¹⁹ J
λ = 19.89 ×10⁻²⁶ Jm / 13.056 × 1.6×10⁻¹⁹ J
λ = 19.89 ×10⁻²⁶ Jm / 20.9 ×10⁻¹⁹ J
λ = 0.95×10⁻⁷ m
m to nm:
0.95×10⁻⁷ m
×10⁹nm/1 m
0.95×10² nm
Frequency:
Frequency = speed of electron / wavelength
by putting values,
Frequency = 3×10⁸m/s /0.95×10⁻⁷ m
Frequency = 3.16 ×10¹⁴ s⁻¹
s⁻¹ = Hz
Frequency = 3.16 ×10¹⁴ Hz
Atoms are electrically neutral because they have equal numbers of protons (positively charged) and electrons (negatively charged).
Answer:
1. Increasing the concentration of the acid
2. Increasing the temperature
Explanation:
CaCO₃ + 2HCl ⟶ CaCl₂ + H₂O + CO₂
Increasing the concentration of the acid increases the number of hydronium ions in contact with the surface of the CaCO₃ per unit time.
Increasing the temperature increases the kinetic energy of the hydronium ions, so they hit the surface of the CaCO₃ mor frequently and with greater force.
3. is wrong. The bigger the pieces, the smaller the surface area that is available for reaction.
The order of the solutions from lowest to highest concentration : A, B, C
<h3>Further explanation</h3>
Given
the following solutions
Required
order of increasing concentration
Solution
Molarity shows the number of moles of solute in every 1 liter of solution.
Solution A : 0.5 moles : 2 L solution = 0.25 M
Solution B : 1 moles : 3 L solution = 0.33 M
Solution C : 1.5 moles : 4 L solution = 0.375 M
