75-Archetype SyllabusChemistry • ARCH-C-15 • Spec C14

Full 6-Card Lesson 15-Question Timed Drill

UAT-UK SPEC CODE: C14 (Metals & The Periodic Table)ASSUMED MATHS 1 PREREQUISITE: M3.4FREQUENCY: MEDIUM

Periodic Table Trends (Groups 1, 17, 18), Metal Reactivity Displacement & Extraction Series

Deconstructed from 9 past UAT-UK questions (4% of all historical Chemistry papers). Students using standard A-Level classroom methods spend an average of 125s on this archetype—blowing past the 90s ESAT budget. Using the 2-line Sub-90 heuristic below compresses solve time to 30s (saving 95s per question).

Historical Frequency

9 Past Qs

4% of Chemistry

Classroom Trap Time

125s

+35s over 90s budget

Sub-90 Target Time

30s

Banks +95s on the clock

Dominant UI Format

1-2-3 Statement

Maths 1 Skill: M3.4

Card 1 & Card 2 Preview: The Classroom Time Trap vs. Sub-90 2-Line Rule

Excerpted from our interactive 6-Step Topic Lesson for ARCH-C-15.

Launch All 6 Active-Recall Cards

CARD 1 OF 6 • THE CLASSROOM TIME TRAP (125s)

Why Students Bleed Time:

Evaluate each statement: Statement 1 is correct (Group 1 metals lose

1

electron; larger atomic radius and increased inner-shell shielding make electron loss easier down the group). Statement 2 is correct (Group 17 halogens gain

1

electron; larger radius and increased shielding weaken attraction for an incoming electron down the group). Statement 3 is correct (metallic bonding weakens down Group 1, so

\text{mp/bp}

decrease). Statement 4 is false (intermolecular forces between

\text{X}_2

molecules strengthen down Group 17 as molecular size increases, so

\text{mp/bp}

increase from

\text{F}_2\text{(g)}

\text{I}_2\text{(s)}

). Thus 1, 2 and 3 only are correct (~95s).

In 9 past UAT-UK questions (4% of Chemistry), candidates lose 95s by down group 1: reactivity increases (easier to lose outer e^-) and mp decreases. down group 17: reactivity decreases (harder to gain outer e^-) and mp/bp increases (stronger intermolecular forces). Instead, apply C14 with Maths 1 skill M3.4.

CARD 2 OF 6 • THE 2-LINE SUB-90 HEURISTIC (<30s)

Line 1 (Reactivity Opposite): Group 1 loses

e^-

(reactivity

\uparrow

); Group 17 gains

e^-

(reactivity

\downarrow

)

\implies

1 & 2 True.

**Line 2 (

\text{mp/bp}

Opposite):** Group 1

\text{mp/bp}

\downarrow

(3 True); Group 17

\text{mp/bp}

\uparrow

(

\text{Cl}_2\text{(g)} \rightarrow \text{Br}_2\text{(l)} \rightarrow \text{I}_2\text{(s)}

, 4 False) (20s).

Sanity & Limit Check: Verify units/signs against sign_or_direction_flip (Assuming Group 17 halogens become more reactive down the group like Group 1 alkali metals (or that Group 1 melting points increase down the group like Group 17)) and multi_statement_linchpin_foil (Claiming aluminium or magnesium is extracted by heating its oxide with carbon in a blast furnace (metals above carbon require electrolysis of molten ore)).

Examiner Distractor Blueprint for ARCH-C-15

FOIL #1sign_or_direction_flip

Assuming Group 17 halogens become more reactive down the group like Group 1 alkali metals (or that Group 1 melting points increase down the group like Group 17)

Down Group 1: reactivity INCREASES (easier to lose outer e^-) and MP DECREASES. Down Group 17: reactivity DECREASES (harder to gain outer e^-) and MP/BP INCREASES (stronger intermolecular forces).

Open Sign / Direction Flip Clinic

FOIL #2multi_statement_linchpin_foil

Claiming aluminium or magnesium is extracted by heating its oxide with carbon in a blast furnace (metals above carbon require electrolysis of molten ore)

Carbon can only reduce oxides of metals BELOW carbon in the reactivity series (Zn, Fe, Sn, Cu); K, Na, Ca, Mg, Al require molten electrolysis.

Open Multi-Statement Linchpin Foil Clinic

FOIL #3multi_statement_linchpin_foil

Claiming zinc sacrificial protection stops iron rusting purely by acting as a physical barrier (ignoring that zinc is more reactive and oxidises preferentially even when scratched)

Because Zn is higher in the reactivity series than Fe, Zn loses electrons in preference to Fe (sacrificial anode protection) even if the coating is scratched.

Open Multi-Statement Linchpin Foil Clinic

FOIL #4table_column_pruning_trap

Solving every pairwise displacement cell in a 4x4 metal/salt matrix instead of counting the number of ✓ reactions per metal (most reactive metal has the most ✓'s)

In a metal vs metal-ion displacement grid, the row with the most reactions is immediately the most reactive metal.

Open Table Column Pruning Trap Clinic

Try 1 Live Sample Question Under the 90-Second Stopwatch

Press W to open the 2-line dry-wipe scratchpad, select A–E, and lock in to reveal the Dual-View solution.

Full 6-Card Lesson Launch All 15 Questions (ARCH-C-15)

ARCH-C-15: Periodic Table Trends (Groups 1, 17, 18), Metal Reactivity Displacement & Extraction Series (Sample)Chemistry

00:00.0

SUB-90 ZONE (<30S)

0.0s30s Sub-9090s ESAT Budget150s Classroom

Question 1 of 1ARCH-C-15 (6-Card Lesson)Format: Standard 5-Option

Right-click any option to cross out • Keys A–E + Enter

Question 1 of 1 • 90s Target

Ready to Start Question 1?

The question stem, diagram, and answer options are hidden behind this pre-start gate. When you click below, the question will reveal and your 90-second split stopwatch will immediately begin ticking.

Chemistry•ARCH-C-15•Standard 5-Option

or press Enter to start