It is the crust, the least dense layer.
Your answer would be D, single replacement
Answer the correct answer out of the four is option c spectroscopy
Explanation- The interaction between electromagnetic radiation and matter studied. This study is commonly known as spectroscopy. It can also be named as study of absorption spectra or emission spectra.
The former spectrum is formed when energy is absorbed from Photons or light energy by electrons while the latter spectrum is formed due to a wavelength of light that is released when electrons jump from higher to lower level.
The number of oxygen atoms is in 5.00 g of sample of sodium dichromate, Na₂Cr₂O₇ is 1.125 x 10²³ atoms.
<h3>What is sodium dichromate?</h3>
Sodium dichromate is an inorganic compound. It is sued in tanning and mental illness.
The molar mass of sodium = 23 gm
The molar mass of Cr = 51.99 gm
The molar mass of oxygen = 16 gm
Molar mass of Na₂Cr₂O₇ = 2(23) + 2(51.99) + 7(16) = 261.98 gm
Number of moles in 7 gm = mass / molar mass = 7 / 261.98 = 0.0267 moles
1 mole of Na₂Cr₂O₇ contains 7 moles of oxygen, therefore:
The number of moles of oxygen in 0.0267 moles = 0.0267 x 7 = 0.1869 moles
Thus, the number of atoms = 0.1869 x 6.02 x 10^23 = 1.125 x 10²³ atoms.
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