Chemistry Unit 6

Question 1

Coulomb’s Law

Answer 1

When attraction goes up, then magnitude goes up and distance^2 goes down.

Question 2

What is atomic radii?

Answer 2

Distance from the center of the nucleus to the boundary of the e- cloud.

Question 3

Atomic radii group trend?

Answer 3

Larger, new energy levels of electrons. d^2 goes up, so attraction goes down. More e- shielding effect also weakening attraction of p+/ve- and increasing distance.

Question 4

Atomic radii period trend?

Answer 4

Smaller, stronger positive to negative attraction from an increase in p+/ve-. Magnitude goes up, so attraction goes up (d^2 goes down).

Question 5

Shielding Effect

Answer 5

The inner (core) electrons cause an interference and block the nucleus (p+) from the outer ve-. The more e-=more shielding effect.

Question 6

What is first ionization energy?

Answer 6

The energy required to remove the most loosely held electron.

Question 7

Ionization energy group trend?

Answer 7

Decreases, added energy level weakens attraction between p=/ve-. More Shielding effect. Easier to remove ve-. Coulombs: d^2 goes up, so attraction goes down.

Question 8

Ionization energy period trend?

Answer 8

Increases, attraction between p+/ve- is greater, more protons(nuclear charge). Harder to remove e-. Coulombs: mag goes up, attraction goes up

Question 9

Electronegativity

Answer 9

Attraction an atom has for a bonding pair of electrons (attract e- towards itself).

Question 10

Electronegativity group trend?

Answer 10

Decreases, less attraction due to e- being further from nucleus. More shielding effect (bigger size). Coulombs: d^2 goes up, so attract goes down

Question 11

Electronegativity period trend?

Answer 11

Increases, added p+/e- so greater attraction for e- (smaller size). Coulombs: magnitude goes up, attraction goes up.

Question 12

What is reactivity?

Answer 12

How completely and easily an atom bonds to another (lose/gain/share).

Question 13

Reactivity METALS group trend?

Answer 13

Increases, larger it is easier to lose e- due to distance and shielding effect.

Question 14

Reactivity METALS period trend?

Answer 14

Decreases, smaller so hold on to e- is stronger due to more p+ and ve-.
Coulombs: magnitude goes up, attraction goes up.

Question 15

Reactivity NONMETALS group trend?

Answer 15

Decreases, larger so less attraction to (others) ve-. Coulombs: magnitude goes up, attraction goes up.

Question 16

Reactivity NONMETALS period trend?

Answer 16

Increases, smaller so more attraction to ve- and others. Coulombs: magnitude goes up, attract goes up.

Question 17

Ionic size as compared to atom; which ANIONS and what is their trend?

Answer 17

(-), gained e- (not p+). NONMETALS larger because gained e-, e- repel other e- and expand. More (-) = larger anion. Cl is smaller and Cl^- is larger.

Question 18

Ionic size as compared to atom; which CATIONS and what is their trend?

Answer 18

(+), lost e- (not p+), METALS smaller because lost electrons. Nucleus can pull e- in closer. more (+) = smaller cation. Fe is larger than Fe^+3.

Question 19

If we make all the atoms ions:

Answer 19

Same trend as atomic radii but it starts over at the staircase.

Question 20

are you ready for the test??

Answer 20

Keep studying!

Question 21

What ions do METALS form?

Answer 21

Cations (+)

Question 22

What ions do NONMETALS form?

Answer 22

Anions (-)

Question 23

What is the periodic law?

Answer 23

When arranged by increasing atomic number, there are chemical and physical properties that repeat periodically.

Question 24

What is a period?

Answer 24

Horizontal

Question 25

What is a group?

Answer 25

Vertical

Question 26

What are representative elements?

Answer 26

Elements in groups 1A-8A

Question 27

What did Dobereiner contribute?

Answer 27

"triad"- three elements with similar properties. Ex: Li, Na, K

Question 28

What did Newlands contribute?

Answer 28

Law of Octaves- Every 8th element, properties repeat. NOT octect rule: atoms gain or lose electrons to obtain 8 valence electrons.

Question 29

What did Meyer contribute?

Answer 29

Arrangement by atomic mass. Chemical properties repeat every so many elements.

Question 30

What did Mendeleev contribute?

Answer 30

Arrangement by INCREASING atomic mass. Predicted unknown elements by leaving spaces in the table. Germanium, Gallium, Scandium

Question 31

What did Moseley contribute?

Answer 31

Arrangement by increasing atomic number.

Question 32

Properties of METALS

Answer 32

small number of ve-, easily lose ve-, cations, good electrical and heat conductors, ductile, malleable, lustrous, solid at room temp

Question 33

Properties of NONMETALS

Answer 33

several ve-, anions, poor conductors of heat and electricity, non-ductile, brittle, not luster, s-l-g at room temp

Question 34

Properties of METALLOIDS

Answer 34

Both metal and nonmetal properties

Question 35

Properties of Alkali metals

Answer 35

soft, very reactive, stored under oil so they don't react

Question 36

Properties of Alkaline earth metals

Answer 36

a little less soft, more mildly reactive, only react at temps when water is steam

Question 37

Properties of Halogens

Answer 37

Very smelly (ew!), burn flesh, does not dissolve well in water, reacts with most metals and many nonmetals

Question 38

Properties of noble gases

Answer 38

Not very reactive, do not like forming compounds with other elements, very stable

Question 39

Lanthanides

Answer 39

rare earth metals, similar across period, all solid

Question 40

Actinides

Answer 40

radioactive, similar across period, all solid

Question 41

Transition metals

Answer 41

contains everyday metals

Question 42

Malleable

Answer 42

bent or shaped easily

Question 43

Ductile

Answer 43

can be stretched into wire

Question 44

Atomic radius

Answer 44

Distance from the middle of the nucleus to the boundary of the electron cloud.