Periodic table arrangement
This group will lose 1 electron to have a full outer shell of electrons
Group 17 (or halogens)
Elements in Group 17 are known as this group.
halogens
Describe the trend of ionization energy across a period and down a group.
Valence electrons are in same energy level so increasing protons leads to greater attraction and higher ionization energy.
Distance of valence energy level from nucleus outweighs increasing nuclear charge. Ionization energy decreases down the group.
Which type of compound(s) is expected to have relatively high melting points?
I. Ionic compounds
II. Metallic compounds
III. Simple covalent molecules
IV. Giant covalent networks
I, II, and IV
Explain the molecular geometry and polarity of carbon dioxide.
linear AND two domains «repel» ✔
non-polar AND polar bonds cancel / symmetrical distribution of charge ✔
This block describes all alkali metals.
s-block
The elements of the d and f block are referred to as ________________ elements.
transition elements
Which best explains the decrease in atomic radius across period 1, 2 and 3?
A. #p+ decrease; #e- decrease; electron shielding increase
B. #p+ decrease; e- in the same energy level; electron shielding is constant
C. #p+ increase; #e- increase; electron shielding decrease
D. #p+ increase; e- in the same energy level; electron shielding is constant
D. p+ increase; e- in the same energy level; electron shielding is constant
Explain why a chlorine atom pulls more strongly on valence electrons?
Greater nuclear charge and smaller distance between nucleus and valence electrons.
Which set of ions shows increasing ionic radii?
A. P3− < Cl− < K+ < Ca2+
B. Cl− < P3− < Ca2+ < K+
C. K+ < Ca2+ < P3− < Cl−
D. Ca2+ < K+ < Cl− < P3−
D. Ca2+ < K+ < Cl− < P3−
Elements in the same _________ usually have the same number of valence electrons and similar reactivity
Group
The periodic table provided shows 118 elements. Which group of elements would a new element with atomic number 119 be most similar to?
A. Alkali metals
B. Halogens
C. Lanthanoids and actinoids
D. Noble gases
A. Alkali metals
Which of the following can be used to determine the group of an element in the periodic table?
I. successive ionization energies
II. electron configuration
III. number of occupied energy levels
I and II
This accounts for why metallic bonds are so strong and why metals are electrically conductive.
sea of delocalized electrons
The difference between first ionization energy and first electron affinity
The first electron affinity is the energy change when 1 mol of electrons is added to 1 mole of gaseous atoms.
X(g) + e- → X-(g) while ionization is the opposite:
SL: Write the electron configuration of zinc AND
HL: Explain why zinc is not truly considered a transition metal.
[Ar] 3d¹⁰ 4s² ; has a full 3d-orbital in all oxidative states.
Which elements are considered to be metalloids?
I. Gallium
II. Germanium
III. Arsenic
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
C. II and III only
Describe the trend for ionic radius compared to atomic radius and describe why this trend is seen.
Ionic radius decreases for cations compared to their atomic radius because negative e- are being removed, increasing e-static attraction between nucleus and outermost e- which are still in the same E lvl
Ionic radius increases for anions compared to their atomic radius because e- are being added, increasing e-/e- repulsion within the same E lvl, thus increasing in radius
Using bonding models, why does NaCl have a higher melting point than CsCl?
NaCl has stronger ionic bonding due to smaller ions, stronger e-static attraction
Describe and explain the molecular geometry for NH3. (3 marks)
Trigonal pyramidal (1). There are 4 electron domains around N (the central atom), one nonbonding pair of e- on N, and 3 bonding pairs N-H (1). Bond angle <109.5 (approx. 107) due to the lone pair on N, resulting in repelling bonding pairs more strongly (1).
Which electron configuration represents a d‑block element in the ground state?
A. 1s22s22p63s23p64s13d1
B. 1s22s22p63s23p64s13d10
C. 1s22s22p63s23p64s23d9
D. 1s22s22p63s23p64s13d104p1
B. 1s22s22p63s23p64s13d10
State a physical property of sulfur which supports its classification as a non-metal element.
Any one of:
insulator/non-conductor «of electricity/heat» OR brittle OR dull ✔
Accept other physical property.
Do not accept answers based on electron configuration
Identify and explain which of the following species would have the largest radius: O2-, F-, Ne, Na+ and Mg2+ (2 marks)
O2- has the largest radius as the species are isoelectronic (have the same number of electrons) but oxygen has the least protons and so less attraction between nucleus and valence electrons.
Using the data from section 9 of the data booklet, explain the trend of first electron affinity going down group 17.
As you move down the group:
(Electron affinity is the energy change when one mole of e- is added to one mole of gaseous atoms to form one mole of gaseous negative ions.) As you go down group 17, electron affinity decreases because:
This weaker attraction makes it less favorable to gain an electron, lowering electron affinity.
Explain why Beryllium behaves differently from other Group 2 elements
small size leading to high polarizing power and covalent character in compounds rather than complete ionic character