Calculate the mass defect for the formation of phosphorus-31. the mass of a phosphorus-31 nucleus is 30.973765 amu. the masses of a proton and a neutron are 1.00728 and 1.00866 amu, respectively. enter your answer in amu's with five decimal places and no units.

The mass defect for the formation of phosphorus-31 is 0.27399

Explanation:

Mass defect is defined as the difference in the mass of an isotope and its mass number.

The equation used to calculate mass defect follows:

where,

= number of protons

= mass of one proton

= number of neutrons

= mass of one neutron

M = mass number of element

We are given:

An isotope of phosphorus which is

Number of protons = atomic number = 15

Number of neutrons = Mass number - atomic number = 31 - 15 = 16

Mass of proton = 1.00728 amu

Mass of neutron = 1.00866 amu

Mass number of phosphorus = 30.973765 amu

Putting values in above equation, we get:

Hence, the mass defect for the formation of phosphorus-31 is 0.27399

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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