The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

The chemical reaction between aqueous magnesium sulfate and aqueous sodium carbonate is represented as:

$MgSO_4(aq)+Na_2CO_3(aq)\rightarrow Na_2SO_4(aq)+MgCO_3(s)$

8 0

3 years ago

using the Bohr model for hydrogen: energy = hc/wavelength = 2.18 x 10^-18 Joules (1/nf2 - 1/ni2) N=15 to n=5

soldier1979 [14.2K]

Answer:

Energy lost is 7.63×10⁻²⁰J

Explanation:

Hello,

I think what the question is requesting is to calculate the energy difference when an excited electron drops from N = 15 to N = 5

E = hc/λ(1/n₂² - 1/n₁²)

n₁ = 15

n₂ = 5

hc/λ = 2.18×10⁻¹⁸J (according to the data)

E = 2.18×10⁻¹⁸ (1/n₂² - 1/n₁²)

E = 2.18×10⁻¹⁸ (1/15² - 1/5²)

E = 2.18×10⁻¹⁸ ×(-0.035)

E = -7.63×10⁻²⁰J

The energy lost is 7.63×10⁻²⁰J

Note : energy is lost / given off when the excited electron jumps from a higher energy level to a lower energy level

5 0

3 years ago