Powerpoint_homework_40to59

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Suppose you have just discovered three new elements. Element 1
is a solid at room temperature, a fair conductor of heat and electricity,
and not ductile. Element 2 is a solid at room temperature and
shiny. Element 3 is a gas at room temperature and a poor
conductor of heat and electricity. Classify each element as
either a metal, non-metal, or metalloid.
A certain element belongs to the p-block. It exhibits only moderate
conductivity, is a solid at room temperature, and is not malleable
or ductile. Further, it contains 4d electrons, but not 5d electrons.
It is also known not to have chemical properties similar to those
of nitrogen. Identify the element and explain your reasoning.
#40 Why is there a large increase in between the first and second
ionization energies of the alkali metals?
Answer:
The alkali metals
LOVE to lose ONE
electron to vacate
the s-orbital that
they have half-filled.
But to lose TWO
electrons would
be too many. They
want to achieve the
noble gas electron
configuration.
#41 How does the ionic radius of a typical metal compare with its
atomic radius?
For Metals,
the ionic radius is
much smaller
because metals
tend to LOSE
electrons from
their outermost
energy level.
#42 Which particle has the larger radius in each atom/ion pair?
a. Na, Na+
Na
#42 Which particle has the larger radius in each atom/ion pair?
b. S, S-2
-2
S
#42 Which particle has the larger radius in each atom/ion pair?
c. I, I-1
-1
I
#42 Which particle has the larger radius in each atom/ion pair?
d. Al, Al+3
Al
43. Which element in each pair has a higher electronegativity value?
Cl and F
F
43. Which element in each pair has a higher electronegativity value?
C and N
N
43. Which element in each pair has a higher electronegativity value?
Mg and Ne
Mg
43. Which element in each pair has a higher electronegativity value?
As and Ca
As
#44 Why are noble gases not included in table 6.2?
#45 When the elements in each pair are chemically combined
which element in each pair has a greater attraction for electrons?
The one with the highest electronegativity
Ca or O
O
#45 When the elements in each pair are chemically combined
which element in each pair has a greater attraction for electrons?
The one with the highest electronegativity
O or F
F
#45 When the elements in each pair are chemically combined
which element in each pair has a greater attraction for electrons?
The one with the highest electronegativity
H or O
O
#45 When the elements in each pair are chemically combined
which element in each pair has a greater attraction for electrons?
The one with the highest electronegativity
K or S
S
#46 For which of these properties does lithium have a larger value than
potassium?
a. first ionization energy?
#46 For which of these properties does lithium have a larger value than
potassium?
b. atomic radius?
#46 For which of these properties does lithium have a larger value than
potassium?
c. electronegativity?
#46 For which of these properties does lithium have a larger value than
potassium?
d. ionic radius?
47 The bar graph shows how many elements were discovered
before 1750 and in each 50 year period between 1750 and 2000
a. In which 50 year period were the most elements discovered?
b. How did Mendeleev’s work contribute to the discovery of
elements?
c. What percentage of the elements were discovered by 1900?
48. Write the symbol of the element or elements that fit each
description:
4A
a. a nonmetal in group 4A
48. Write the symbol of the element or elements that fit each
description:
b. the inner transition metal with the lowest atomic number.
48. Write the symbol of the element or elements that fit each
description:
c. all of the nonmetals for which the atomic number is a multiple of five.
48. Write the symbol of the element or elements that fit each
description:
d. a metal in group 5A
Bi
#49 In which pair of elements are the chemical properties of
the elements most similar? Explain your reasoning.
a. sodium and chlorine
c. boron and oxygen
b. nitrogen and phosphorus
#50 Explain why fluorine has a smaller atomic radius than both
oxygen and chlorine.
Flourine is smaller than oxygen
because it has more protons
pulling the electrons in tighter.
It is smaller than chlorine
because it has 8 fewer
electrons.
#51 Would you expect metals or nonmetals in the same
period to have higher ionization energies? Give a reason for
your answer.
NON_METALS
because the non-metals want to retain
electrons and even get more electrons
not lose them.
#52 In each pair, which ion is larger?
+2
Ca
+2
Mg
Ca
#52 In each pair, which ion is larger?
-1
Cl
-3
P
-3
P
#52 In each pair, which ion is larger?
Cu+1
+2
Cu
+1
Cu
#53 List the symbols for all the elements with electron config.
that ends as follows. Each n represents an energy level.
a. ns1
#53 List the symbols for all the elements with electron config.
that ends as follows. Each n represents an energy level.
b. ns2np4
#53 List the symbols for all the elements with electron config.
that ends as follows. Each n represents an energy level.
c. ns2nd10
d orbitals are always lower
than s or p orbitals!
#54 Explain why there should be a connection between an
element’s electron configuration and its location on the periodic
table.
An element’s electron configuration determines
its location (group) in the periodic table. It tells
us how many valence electrons (s and p sublevel).
#55 Which equation represents the first ionization of an alkali
metal atom?
a. Cl NO, chlorine is not an alkali metal (it is a halogen)
b. Ca
NO, calcium is not an alkali metal (it is an alkaline earth metal)
c. K
K+1 + eone electron.
Yes this is an alkali metal and it is giving off
d. H
H+1 + e- NO, Hydrogen is not considered an alkali
metal even though it is often listed in the same group
#56 Use the graph in Fig 6.14 to estimate the atomic radius
of the indium atom.
Indium is Number 49 It appears to have a radius of about 170 pm.
#57 What trend is demonstrated by the following series of
equations?
Li + 520 kJ/mol
O + 1314 kJ/mol
F + 1681 kJ/mol
Ne + 2080 kJ/mol
Li+1
This information shows that ionization
energy increases as you go across a
period from left to right.
e-
+
O+1 + eF+1 + eNe+1 + e-
F
O
#58 There is a large jump between the second and third ionization
energies of magnesium. There is a large jump between the third
and fourth ionization energies of aluminum. Explain these observations.
Magnesium has TWO valence electrons (3s2)
It doesn’t mind losing those two because then
it has 10 electrons…the same as NEON, a noble
gas. But it doesn’t want to lose a THIRD!!
#58 There is a large jump between the second and third ionization
energies of magnesium. There is a large jump between the third
and fourth ionization energies of aluminum. Explain these observations.
Aluminum has THREE valence electrons (3s23p1)
It doesn’t mind losing those three because then
it has 10 electrons…the same as NEON, a noble
gas. But it doesn’t want to lose a FOURTH!!
#59 The bar graph shows the relationship between atomic and ionic
radii for Group 1A elements.
a. Describe and explain the trend in atomic radius within the group.
The atomic radius increases from top
to bottom within the group.
#59 The bar graph shows the relationship between atomic and ionic
radii for Group 1A elements.
b. Explain the difference between the size of the atoms and the sizes
of the ions.
The since alkali metals all tend
to lose one electron, they become
smaller because that outer s orbital
is now gone.
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