Na₂S(aq) + Cd(NO₃)₂(aq) = CdS(s) + 2NaNO₃(aq)
v=25.00 mL
c=0.0100 mmol/mL
M(Na₂S)=78.046 mg/mmol
n(Na₂S)=n{Cd(NO₃)₂}=cv
m(Na₂S)=M(Na₂S)n(Na₂S)=M(Na₂S)cv
m(Na₂S)=78.046*0.0100*25.00≈19.5 mg
3.98 x 10⁻¹⁹ Joule
<h3>Further explanation</h3>
<u>Given:</u>
The green light has a frequency of about 6.00 x 10¹⁴ s⁻¹.
<u>Question:</u>
The energy of a photon of green light (in joules).
<u>The Process:</u>
The energy of a photon is given by 
- E = energy in joules
- h = Planck's constant 6.63 x 10⁻³⁴ Js
- f = frequency of light in Hz (sometimes the symbol f is written as v)
Let us find out the energy of the green light emitted per photon.

Thus, we get a result of 
- - - - - - - - - -
Notes
- When an electron moves between energy levels it must emit or absorb energy.
- The energy emitted or absorbed corresponds to the difference between the two allowed energy states, i.e., as packets of light called photons.
- A higher energy photon corresponds to a higher frequency (shorter wavelength) of light.
<h3>Learn more</h3>
- The energy of the orange light emitted per photon brainly.com/question/2485282#
- Determine the density of our sun at the end of its lifetime brainly.com/question/5189537
- Find out the kinetic energy of the emitted electrons when metal is exposed to UV rays brainly.com/question/5416146
Keywords: green light, frequency, the energy, a photon, Planck's constant, electrons, emitted, wavelength, joules
Answer: The millimoles of sodium carbonate the chemist has added to the flask are 256
Explanation:
Molarity is defined as the number of moles dissolved per liter of the solution.
To calculate the number of moles for given molarity, we use the equation:
.....(1)
Molarity of
solution = 1.42 M
Volume of solution = 180.0 mL
Putting values in equation 1, we get:

Thus the millimoles of sodium carbonate the chemist has added to the flask are 256.
Pv =nRT
T= 273
n = 0.500
v= 11.2
R= 0.08206
p= 0.5×0.08206×273 ÷ (11.2) =10.00