CZ forms the largest cation.[1]
The big jump in successive ionisation energies shows the number of outer electrons. V jumps after IE4 (silicon), W after IE2 (magnesium, an alkaline earth metal), Y after IE1 (sodium) and Z after IE3 (aluminium). X shows no jump in the first five, so it lies near the end of the period.
Z is aluminium, and Al3+ is the smallest of these cations, not the largest, so C is false. X has the greatest nuclear charge of the five and the same number of shells, so it has the smallest radius.
BIt can form a chloride with the formula QCl5.[1]
The big jump is after the 5th ionisation energy, so Q has 5 valence electrons and is in Group 15. Below Period 2 it can expand its octet and form QCl5.
A Group 15 oxide is acidic, not basic. The atomic numbers of Group 15 elements (7, 15, 33, 51, 83) are odd. QCl3 is pyramidal, not trigonal planar.
DSodium's electron is closer to the nucleus.[1]
Na+ must lose an electron from the inner 2p subshell, close to the nucleus and little shielded.
Mg+ still has a 3s electron in the outer shell, which is far easier to remove.
B1 and 2 only[1]
Rb+ has lost its outer shell, so it is smaller than the atom. Br− has an extra electron, so it is larger.
Br− and Rb+ have the same electrons, but Br has 35 protons and Rb 37, so Br− is the larger ion.
Bmelting points decrease[1]
Melting points rise from sodium to silicon and only then fall.
The other three are true trends.
AR, Q, P, S[1]
R is sodium, Q is silicon (SiO2), P is phosphorus or sulfur (acidic oxide) and S is argon.
Na (11), Si (14), P or S (15 or 16), Ar (18).
Arow A[1]
SO3 gives sulfuric acid (pH 1). SiO2 is insoluble (pH 7).
MgO is sparingly soluble (pH 9) and Na2O gives NaOH (pH 13).
Dacidity decreases[1]
The acidity increases across the period: NaCl gives pH 7 and PCl5 pH 2.
SiCl4 + 4H2O → SiO2·2H2O + 4HCl, Al2O3 is amphoteric, and 2NaOH + H2SO4 gives neutral Na2SO4.
AZ, X, W, Y[1]
Z is sodium (Na2O), X aluminium (amphoteric), W silicon (SiO2 needs concentrated alkali) and Y phosphorus or sulfur.
In order: Na, Al, Si, then P or S.
AX < Y < Z[1]
Z is sodium, Y aluminium and X a non-metal further right.
Atomic radius decreases across the period, so X is smallest and Z largest.
CG, F, E, H[1]
G, with the lowest electronegativity, is furthest left (sodium). F is aluminium. H, the smallest atom, is furthest right.
E has an acidic chloride and lies between: G, F, E, H.
Cthe oxide gives an acidic solution[1]
A, B and D describe aluminium: a conducting metal, AlCl3 hydrolyses to pH 3, and Al(OH)3 dissolves in excess alkali.
Aluminium oxide is insoluble in water, so C does not fit.
Athe oxide dissolves in dilute NaOH[1]
B, C and D describe silicon: SiCl4 is a liquid that hydrolyses to pH 2, and SiO2 is giant covalent.
SiO2 reacts only with hot concentrated alkali, so A does not fit.
A1 only[1]
Z is silicon, a solid.
SiO2 is insoluble in water, and silicon forms only SiCl4.
BIt is amphoteric.[1]
Y is silicon, so X is aluminium.
Aluminium oxide, Al2O3, is an amphoteric, giant ionic solid.
CN, O, M[1]
N has a basic oxide (a metal on the left), O an amphoteric oxide (aluminium) and M an acidic oxide (a non-metal on the right).
Across a period oxides change from basic to amphoteric to acidic: N, O, M.
Breducing power decreases[1]
The two outer electrons are lost more easily down the group, so the reducing power increases.
The carbonates give a white oxide and carbon dioxide, an acidic gas, and the solutions with water become more alkaline.
Dthermal stability of the carbonate[1]
The larger M2+ ion polarises the carbonate ion less, so the carbonate is more stable.
Charge density, electronegativity and melting point all generally decrease.
B1 and 2 only[1]
Smaller, doubly charged ions and two delocalised electrons per atom give stronger metallic bonding.
Ionisation energy is not what holds the lattice together.
Abromine is decolourised by NaCl[1]
Bromine is less reactive than chlorine, so it cannot displace chlorine: nothing happens and the solution stays orange.
AgCl is a white precipitate, chlorine oxidises thiosulfate to sulfate (white BaSO4), and chlorine displaces brown iodine.
Drow D[1]
Potassium is below sodium, so it is more reactive. Lithium is less reactive.
Z displaces Y from its salt, so Z is more reactive than Y: chlorine displaces iodine from KI.
BS, R, Q, T[1]
Q displaces T, so Q is above T. Q cannot displace R, so R is above Q.
A carbonate that does not decompose belongs to a very reactive metal, so S is at the top: S, R, Q, T.
AQ is high up in the series.[1]
Only metals above carbon need electrolysis, so Q is very reactive.
R is found uncombined, so it is unreactive and below hydrogen. Q's compounds are the hardest to break down.
DIron corrodes in place of copper.[1]
Iron is above copper in the reactivity series, so it loses electrons more readily.
In contact with copper, iron acts as the sacrificial metal and corrodes instead.