entry task: friday november 2 nd which of the following pair has a smaller radius? sr or sr +2 p or...
TRANSCRIPT
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%