Most neutral atoms of fluorine have an atomic mass of 19 amu and an atomic number of 9. What are these atoms composed of?
O A. protons, 19 neutrons, and 9 electrons
• B. 9 protons, 10 neutrons, and 10 electrons
• c. 9 protons, 10 neutrons, and 9 electrons
O D. 9 protons, 9 neutrons, and 9 electrons

it's c. elements are placed in rows based on how may valencies electrons have.

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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