Answer:
Molar mass of Ca = 40 g / mol , given 123 g Ca is 123/40= 3.075 moles,
1 mole = 6.022 * 10^23 atoms, so 3.075 moles Ca= 18.51*10^23 atoms
Explanation:
Answer:
All elements in the same A group will have the same number of
valence electrons.
Explanation:
Group A has 1 valence electrons.
Answer:

Explanation:
Hello,
In this case, we could considering this as a redox titration:

Thus, the balance turns out (by adding both hydrogen ions and water):

Thus, by stoichiometry, the grams of Fe+2 ions result:

Finally, the mass percent is:

Best regards.
Answer:
The correct answer to the question is
a. it contradicted accepted principles of physics
Explanation:
The idea of electrons moving in orbits contradict classical electromagnetism idea whereby electrons are expected spiral to the nucleus instantaneously. Meaning all atoms are supposed to be unstable a postulation that contradicts observable evidence.
Bohr's model of the atom consists of atoms, having electrons in specific orbits. The theory explains spectroscopy and enabled the determination of the constituent atoms present in distant stars.
<span>Hydrogen atoms accompany electrons as they are transferred in biological systems in order to ensure that the metabolism proceeds to completion.
This is considered the main purpose of the electron shuttles.
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