The 4 main one are Iron, oxygen, silicon, and magnesium<span />
Answer:
The energy difference between these 2p and 2s orbitals is 
Explanation:
Wavelength of the photon emitted = 
Energy of the photon will corresponds to the energy difference between 2p and 2s orbital = E
Energy of the photon is given by Planck's equation:
h = Planck's constant = 
c = Speed of the light = 
The energy difference between these 2p and 2s orbitals is
If you start with 40.0 grams of the element at noon, 10.0 grams
radioactive element will be left at 2 p.m. The correct answer between
all the choices given is the second choice or letter B. I am hoping that this
answer has satisfied your query and it will be able to help you in your
endeavor, and if you would like, feel free to ask another question.
Water containing carbonic acid and calcium
The molar mass of carbon is 12, hydrogen is 1, and
nitrogen is 14, hence the ratio are:
C = 38.65 / 12 = 3.22
H = 16.25 / 1 = 16.25
N = 45.09 / 14 = 3.22
Divide the three by the lowest ratio which is 3.22:
C = 3.22 / 3.22 = 1
H = 16.25 / 3.22 = 5
N = 3.22 / 3.22 = 1
So the empirical formula is:
CHN
