[🧪] Periodicity/Period 3 Flashcards
What is the general trend in
melting points in Period 3?
[🧪] Periodicity/Period 3
Across the period, melting point increases up till Si, then decreases after Si
metallic bonding → giant molecular → simple molecular
What is the general trend in Period 3 for
electrical conductivity?
Across the period, electrical conductivity increases from Na to Al, then decreases after Al
What is the general trend in Period 3 for
ionic radius?
Decreases from Na+ to Si4+, then increases significantly to P3-, then decreases from P3- to S2-
Describe the visual observations when
sodium reacts with oxygen
- vigorous reaction
- bright yellow flame
- Na₂O formed (white solid)
Describe visual observations when
magnesium reacts with oxygen
- vigorous reaction
- burns with a bright white flame
- MgO formed (white solid)
Describe the visual observations for when
powdered aluminium reacts with oxygen
- fast reaction
- bright white flame
- Al₂O₃ formed (white powder)
Describe the visual observations for when
silicon reacts with oxygen
- slow reaction
- bright white sparks
- SiO₂ formed (white powder)
Conditions for the reaction between aluminium and oxygen
Powdered aluminium
Conditions for the reaction between silicon and oxygen
Powdered silicon and strong heating
Describe the visual observations for when
phosphorus reacts with oxygen
- vigorous reaction
- yellow or white flame
- P₄O₁₀ formed (seen as white clouds)
What is the product of phosphorous reacting with oxygen?
P₄O₁₀
Describe the visual observations for when
sulfur reacts with oxygen
- gentle reaction
- blue flame
Conditions for the reaction between sulfur and oxygen?
Powdered sulfur
Describe the reaction of sodium, magnesium and aluminium with chlorine gas
Vigorous
Describe the reaction of silicon and phosphorous with chlorine gas
Slow