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Flashcards in S-block Deck (10)
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Group 1

Alkali metals (form alkaline hydroxides with water)
s1 e- configuration
+1 oxidation state
Low ΔΗ IE

1

G1 nitrates

More stable than G2 nitrates
Melt then thermally decompose to form nitrite (NO2-) and O2 (relights a glowing splint)
Eg 2NaNO3 -> 2NaNO2 + O2

2

G1 with O2

More reactive down group
Li- red flame
Na- yellow orange flame
K- lilac flame or melts to potassium peroxide

3

G2

Alkali earth matals (oxides and hydroxides are alkaline)
s2 e- configuration
+2 oxidation state
Low ΔH IE

4

G2 nitrates

Less stable than G1 nitrates
Thermally decomposes to give NO2 (brown gas) O2 (relights glowing splint) the oxide and steam
Eg 2Ca(NO2)2hydrate -> 2CaO + 4NO2 + O2 + 6H2O

5

G2 flame test

Ca- orange red
Sr- crimson
Ba- apple green

6

G2 with water

Be doesn't react
Mg burns with steam-> MgO (white solid) + H2 (few bubbles in cold)
Generally cold water -> hydroxide
Steam-> oxide (hydroxides thermally decompose)

7

G2 with O2

Burns to form simple XO

8

G2 with acid

XCl2 + H2

9

G2 carbonates

Undergo thermal decomposition to form metal oxide + CO2
More stable down group