Periodic Trends

Question 1

What is atomic radii

Answer 1

Size of the atom, from the center of the nucleus to the valence electrons

Question 1

What is ionization energy

Answer 1

The energy requires to remove an electron from an atom

Question 2

What is electronegativity

Answer 2

How much an atom attracts other atoms

Question 3

What is electron affinity

Answer 3

The amount of energy released when the atom gains an electron

Question 4

Atomic radii-period trend, why

Answer 4

Decreases, the protons are attracted to the electrons so the more protons the higher the attractive energies and the valence level is pulled closer to the nucleus

Question 5

Atomic radii-group trend, why

Answer 5

Increases, an energy level is added for each period, increasing size

Question 6

Ionization energy-period trend, why

Answer 6

Increases, when the electrons are closer to the nucleus the attractive energies are higher making it more difficult to remove the electron from the atom

Question 7

Ionization energy-group trend, why

Answer 7

Decreases, in larger atoms the electrons are further from the nucleus, decreasing attractive forces making it easier to remove them from the atom

Question 8

What happens to ionization energy when an electron is removed

Answer 8

Increases

More than one - electrons repel each other so when one is removed they sink closer in toward the nucleus
One - there is one less energy level

With electrons closer to the nucleus it’s harder to remove them

Question 9

Electronegativity-period trend, why

Answer 9

Increases (with exceptions), with a smaller size the nucleus is closer to the outside of the atom

Question 10

Electronegativity-group trend, why

Answer 10

Decreases or stays the same (with exceptions), with a larger size the nucleus is further from the outside of the atom

Question 11

Metal reactivity-period trend, why

Answer 11

Decreases, across periods size decreases which means more energy is needed to remove an atom/react so there is a smaller reaction

Question 12

Metal reactivity-group trend, why

Answer 12

Increases, down groups size increases which means less energy is needed to remove an atom/react so there is a bigger reaction

Question 13

Nonmetal reactivity-period trend, why

Answer 13

Increases, the size of the atom is smaller so it has a higher ability to attract electrons making it more reactive

Question 14

Nonmetal reactivity-group trend, why

Answer 14

Decreases, the size of the atom is larger so it has a decreased ability to attract electrons making it less reactive

Question 15

Electron affinity-period trend, why

Answer 15

Increases, the atoms are smaller with a higher ability to attract electrons so there is more energy released when one is gained

Question 16

Electron affinity-group, why

Answer 16

Decreases, the atoms are larger with a decreased ability to attract electrons so there is less energy released when one is gained

Question 17

How do you determine the number of protons

Answer 17

The atomic number

Question 18

How do you determine the number of electrons

Answer 18

Atomic number

Question 19

How do you determine the number of neutrons

Answer 19

Subtract the number of protons from the weight (number next to element name)

Question 20

How do you determine the number of valence electrons

Answer 20

One’s digit of the group number, unless they are in groups 3-12, then it is unknown

Question 21

How do you determine energy levels

Answer 21

The period number