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2 years ago

How does one determine the number of core electrons an atom has?

Chemistry

2 answers:

scoundrel [369]2 years ago

4 0

Answer: Subtract the number of valence electrons(outer most shell electrons) from the atomic number of an atom.

Explanation: The total number of electrons for an atom equals to its atomic number. Electrons are present in different shells. Electrons present in outer most shell(valence shell) are known as valence electrons and rest of the electrons present in inner shells are known as core electrons.

So, to determine the number of electrons we subtract the valence electrons from atomic number.

For example, atomic number of N (nitrogen) is 7. It has 5 valence electrons.

Number of core electrons for N = 7 - 5 = 2

Aleonysh [2.5K]2 years ago

3 0

Subtract the group number from the atomic number.

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Ahat [919]

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3 years ago

Which statement applies to electronegativity?

densk [106]

Answer: The correct answer is Option A.

Explanation:

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2 years ago

Which of the following are compounds? (Select all that apply.) CO2 Cl2 Ne NaCl

beks73 [17]

CO2 and NaCl are both compounds

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2 years ago

An atom that normally has __________ electrons in its outer (valence) shell tends not to form chemical bonds with other atoms.

goblinko [34]

8 valence shell electrons.

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3 years ago

If the half-life of a radioactive substances is 590 million years and you have 40 atoms of it, how many half-lives will have pas

Nady [450]

Answer:

Explanation:

Applying,

$2^{n'}$ = R/R'............... Equation 1

Where n' = number of halflives that have passed, R = Original atom of the substance, R' = atom of the substance left after decay.

From the question,

Given: R = 40 atoms, R' = 5 atoms

Substitute these values into equation 1

$2^{n'}$ = 40/5

$2^{n'}$ = 8

$2^{n'}$ = 2³

Equation the base,

n' = 3

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2 years ago