What is the nuclear symbol that represents 26 protons, 30 neutrons, and 23 electrons?

• 
• 
• 
• 

In terms of subatomic particles, what does Cr-54 (atomic number = 24) and Co-57 (atomic number = 27) have in common?

• same number of protons in the nucleus

• same number of neutrons in the nucleus

• same number of electrons in the electron cloud

• same number of subatomic particles in the nucleus

How many electrons does this ion have?

• 82

• 84

• 80

• 204

Which of the following could be the correct Bohr model for fluorine?

• 
• 
• 
• 

What will happen to the atom represented by the Bohr model when it ionizes? Select all that applies.

• It will gain 2 electrons

• It will have 8 valence electrons

• It will develop a -2 charge

• It will be a cation

• It will be an anion

Could this element represented by the Bohr model be boron (B)?

• No, Lewis structures only show valence electrons so this must be an element from group 15.

• Yes, boron has 5 electrons.

A student made the statement that a nitrogen had 5 valence electrons and gained 3 electrons to form a -3 charge. Which of the statements below is a true statement?

• The nitrogen atom gained 3 electrons to empty the outer shell.

• The nitrogen atom gained 3 electrons in order to have 8 valence electrons.

• The statement is incorrect because nitrogen would lose 5 valence electrons and develop a +5 charge.

• The statement is not true because nitrogen would form a +3 charge.

Why does atomic radius increase down a group?

• The number of particles in the nucleus increases.

• The number of valence electrons increases.

• The attractive force between the nucleus and the valence electrons decreases.

• The repulsive force between the inner electrons and the valence electrons decreases.

What do phosphorus, sulfur, and chlorine all have in common? Select all that apply.

• They are all nonmetals

• Their valence electrons are located in the 3rd energy level

• They are all metals

• They all have 3 valance electrons

Why does electronegativity increase from left to right across the periodic table?

• an increase in the size of the nucleus

• an increase in the number of electrons

• an increase in the number of protons

• a decrease in shielding