Entry Task: Friday November 2nd

Which of the following pair has a smaller radius?

Sr or Sr+2 P or P-3 Na or Na+

Periodic Trends Handout Answers

Define periodic law.

Periodic Law- is the periodic repetition of chemical and physical properties of elements by atomic number

Provide 5 properties of a metal Conductive

Have Luster- shiny

Malleable (smack it with hammer and it will flatten out)

Solids at room temperature (except for Mercury)

Loses valence electrons easy.

Provide 5 properties of a nonmetal Non-Conductive

Lack Luster- dull

Not Malleable (as a solid- if smack it with hammer it will shatter)

Most are gases at room temperature.

Does not lose valence electrons easy.

What are metalloids?Elements that have both metal and nonmetal properties

Identify each element as a metal, metalloid, or nonmetal.

Nonmetala) fluorine______

b) germanium ______

c) zinc ______

d) phosphorous______

e) lithium______

Metalloid

Metal

Nonmetal

Metal

a) noble gases ______

b) halogens ______

c) alkali metals ______

d) alkaline earth metals ______

Give two examples of elements for each category.

He, Ne, Ar, Kr, Xe, Rn

F, Cl, Br, I

Li, Na, K, Rb, Cs, Fr

Be, Mg, Ca, Sr, Ba, Ra

What are valence electrons

They are the outer most set of electrons. OR the electrons in the highest principle orbit.

What happens to the reactivity of an element as you move from left to right across the periodic table?

EXPLAIN WHY THIS HAPPENS.

The reactivity decreases, because they are gaining valence electron Or becoming more stable.

What is the octet rule?

The octet rule states that elements that have a filled valence orbit, 8 electrons, will have a stable (non-reacting) arrangement.

What trend in atomic radius do you see as you go down a group/family on the periodic table?

Its increases (gets bigger).

What causes this trend?

The orbit size increases as move down a group.

What trend in atomic radius do you see as you go across a period on the periodic table?

Its decreases (gets smaller).

What causes this trend?

The electrons/protons increases and the nucleus pulls the electrons to it.

a) Al or B ______

b) S or O ______

c) Br or Cl ______

d) Na or Al ______

e) O or F ______

f) Mg or Ca ______

Circle the atom in each pair that has the largest atomic radius

Al - larger orbit

S - larger orbit

Br - larger orbit

Na - less pull from nucleus

O - less pull from nucleus

Ca - larger orbit

Which ions are larger, cations or anions? Explain why.

Anions are larger.

They have gained electrons therefore making them larger.

a) N or N-3 ______

b) Li or Li+1 ______

c) O or O-2 ______

d) Mg or Mg+2 ______

e) Al or Al+3 ______

Circle the atom or ion that is LARGER of the pair.

N-3 - gained electrons

Li - did NOT lose electrons

O-2 - gained electrons

Mg - did not lose electrons

Al - did not lose electrons

Define ionization energy.

It is the energy required to remove one electron.

Is it easier to form a positive ion with an element that has a high ionization energy or an element that has a low ionization energy? Explain.

It is easier with a low ionization energy.

These element with low ie are trying to get rid of electrons to become stable.

What trend in ionization energy do you see as you go down a group/family on the periodic table?

Its decreases (gets less).

What causes this trend?

Large orbits have lots of electrons- easy pickin’s.

What trend in ionization energy do you see as you go across a period on the periodic table?

Its increases (needs more energy).

What causes this trend?

Increasing the # of valence OR becoming more nonmetals so they don’t want to give up electrons.

a) Li or Be ______

b) Na or K ______

c) Cl or Si ______

d) Ca or Ba ______

e) P or Ar ______

f) Li or K ______

Circle the atom in each pair that has the greater ionization energy.

Be - closer to nonmetals

Na - have fewer electrons

Cl - need one more to be stable

Ca - have fewer electrons

Ar - its got the set- back off

Li - fewer electrons

Define Electronegativity.

The ability of an atom to attract electrons in a chemical bond.

What trend in electronegativity do you see as you go down a group/family on the periodic table?

Its decreases (gets less).

What causes this trend?

Large orbits have lots of electrons not really needing electrons.

What trend in electronegativity do you see as you go across a period on the periodic table?

Its increases.

What causes this trend?

Moving towards the nonmetals and they want to fill valence orbit.

a) Ca or Ga ______

b) Li or O ______

c) Cl or Si ______

d) Br or As ______

e) Ba or Sr ______

f) O or S______

Circle the atom in each pair that has the greater electronegativity.

Ga - closer to nonmetals

O - closer to nonmetals

Cl - need one more to be stable

Br - closer to nonmetals

Sr - Fewer electrons

O - fewer electrons

To Know listConcentration of MOSTLY Ch. 6 (75%)

◦Groups/Families verses periods◦Metals, nonmetals and metalloid properties◦# of valence electrons for groups◦Atomic Radius trends◦Ion trends (cation + and anion -)◦Ionization energy- define and trends◦Electronegativity- define and trends

To Know listConcentration of MOSTLY Ch. 6 (75%)

◦Energy levels-light, E-dot/valence-Ch. 5◦Particles- Protons, Electrons Neutrons-Ch. 4◦Physical chemical properties/changes-Ch. 3◦Scientific notation and Significant Figs- Ch. 2

25%