inorganic Flashcards
melting point from Na to Al
-melting points increase from Na to Al
-because all three are only metallic bonding
-which increases across the period due to higher charge density
melting point at Si
-melting point increases significantly at Si
-because it is a macromolecular structure
-which has very strong pure covalent bonds
-that require a lot of energy to break
melting point at p
-melting point decreases significantly at p
-because it is only a simple covalent structure
-with only weak Van der Waals
melting point from S to Ar
-S has the highest melting point of the non-metal elements
-Cl is next
-Ar has the lowest melting point because it is the smallest (monatomic)
-Van der Waals forces are determined by size
;why does sulfur have slightly higher melting point than phosphorous
-Because S is larger than P
-S has 8 atoms whilst P has 4
-thus VDW forces are stronger
Trend in first ionisation energy across period 3
-increase across the period
-increased nuclear charge so stronger attraction between the nucleus and electrons
-radius decreased as a result
-no shielding across the period thus does not affect
trend in atomic radius across period 3
-decreases across period 3
-because proton is added each time
-so stronger attraction between positive nucleus and negative electrons
Reaction of Al with oxygen
burns vigorously with bright white flame
forms 2Al2O3
Reaction of Si with oxygen
burns with a bright white flame and white smoke
forms SiO2
Reaction of Na with oxygen
burns vigorously with yellow flame
forms 2Na2O
Reaction of Mg with oxygen
burns vigorously with a bright white flame
forms 2MgO
Reaction of P with oxygen
burns spontaneously with a bright white flame and smoke
forms P4O10
Reaction of S with oxygen
burns with a blue flame
forms SO2
Reaction of Na with water
2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)
Reaction of Mg with water
Slow in cold water:
Mg(s) + 2H20(l) → Mg(OH)2(aq) + H2(g)
Vigorous with steam:
Mg(s) + H20(l) → MgO(s) + H2(g)
Reaction of Cl with water
dissolves to form chlorine water:
Cl2(aq) + H2O(l) ⇌ HClO(aq) + HCl(aq)
Properties of Na20
bonding: ionic
structure: giant ionic lattice
melting point: high
Properties of MgO
bonding: ionic/covalent
structure: giant ionic lattice
melting point: high
Why is the melting point higher for Mg than for Na?
- Mg is smaller than Na
- Mg has a plus 2 charge whilst Na has a plus 1 charge
- so… stronger attraction between ions in MgO = higher melting point
Properties of Al2O3
bonding; ionic/covalent
structure: giant ionic lattice
melting point: high
Properties of SiO2
bonding: covalent
structure: giant covalent/ macromolecular
melting point: high
Properties of P4O10
bonding: covalent
structure: molecular
melting point: relatively low
properties of SO2 and SO3 and the difference between them
bonding: covalent
structure: molecular
melting point: relatively low
difference: SO2 is a gas at room temperature whilst SO3 is a liquid at room temperature
Reaction of NA2O with water
-ions present after reaction
-type of solution
-pH
Na+ (aq)
OH− (aq)
strongly alkaline
pH 13-14
Reaction of MgO with water
-ions present after reaction
-type of solution
-pH
Mg2+ (aq)
OH- (aq)
moderately alkaline
pH 10
Reaction of Al2O3 with water
-ions present after reaction
-type of solution
-pH
insoluble
pH 7
Reaction of SiO2 with water
-ions present after reaction
-type of solution
-pH
insoluble
pH 7
Reaction of P4O10 with water
-ions present after reaction
-type of solution
-pH
H+ (aq)
H2PO4- (aq)
strongly acidic
pH 0-1
Reaction of SO2 with water
-ions present after reaction
-type of solution
-pH
H+ (aq)
HSO3- (aq)
weakly acidic
pH 2-3
Reaction of SO3 with water
-ions present after reaction
-type of solution
-pH
H+ (aq)
HSO4-
strongly acidic
pH 0-1
what are the four chemical properties of transition metals
- can form complex ions
- can form coloured ions
- variable oxidation states
- catalytic activity
What are the two exceptions- they are not transition metals
Scandium and Zinc
Why are variable oxidation states possible
3d and 4s sublevels are very close in energy thus the electron can be lost from either
Shapes of complex ions: LINEAR
- coordination number of 2
- 180 degrees
Shape of complex ions: TETRAHEDRAL
- coordination number of 4
- 109.5 degrees
- most common with 4
Shape of complex ions: SQUARE PLANAR
- coordination number of 4
- 90 degrees
Shape of complex ions: OCTAHEDRAL
- coordination number of 6
- 90 degrees
What are all the trends going down group 2?
- atomic radius increases
- shielding increases
- reactivity increases
- ionisation energy decreases
- melting point decreases
- solubility of hydroxides increases
- solubility of sulphates decreases
what is the general equation for group 2 metals reacting with water
metal + 2water —-> metal(OH)2 + H2
what happens when magnesium reacts with water
two reactions:
1. with cold water- much slower
Mg + 2H2O —-> Mg(OH)2 + H2
2. with steam- much faster
Mg + H2O —-> MgO + H2
what is the other exception in the reaction with water
Beryllium
Be + H2O —-> BeO + H2
when are group 2 metals used in medicine
- Mg(OH)2. is the least soluble hydroxide so is used as an antacid as it can neutralise stomach acids without dissolving into the bloodstream
- BaSO4. Is the least soluble sulphate so is used as a barium cookie as a medical tracer. If dissolved into the bloodstream it would be toxic however its insolubility prevents this.
when are group 2 metals used in agriculture and industry
- Mg(OH)2 is the least soluble hydroxide so is used in agriculture to neutralise acidic soils
- Magnesium can also be used in the extraction of titanium via a displacement reaction.
TiCl4 + 2Mg —-> 2MgCl2 + Ti
what is the equation for the reduction of vanadium from yellow to blue
Write out
what is the equation for the reduction of vanadium from blue to green
write out
What is the original aqueous solution for Copper(ll) both colour and equation
blue solution
write out
what is the colour and equation of copper (ll) after addition of NaOH
blue ppt
write out
what is the colour and equation of copper (ll) after addition of excess NaOH
no further change
What is the colour and equation of copper (ll) after addition of NH3
blue ppt
write out
What is the colour and equation of copper (ll) after addition of excess NH3
deep blue solution
write out
What is the colour and solution of copper (ll) after addition of Na2CO3
green-blue ppt
write out
what is the equation that happens when excess NH3 is added to copper(ll) hexaqua complex
Cu(H2O)4(OH)2 + 4NH3 —> [Cu(H2O)2(NH3)4]2+ + 2H2O + 2OH-
What is the equation that happens when NaOH is added to copper(ll) haxaqua complex
[Cu(H2O)6]2+ + 2NaOH —> Cu(H2O)4(OH)2 + 2H2O
what is the equation that happens when NH3 is added to copper(ll) haxaqua complex
[Cu(H2O)6]2+ + 2NH3 —> Cu(H2O)4(OH)2 + 2NH4+
What is the equation that happens when Na2CO3 is added to copper(ll) hexaqua complex
[Cu(H2O)6]2+ + CO3 2- —> CuCO3 + 6H2O
What is the original aqueous solution for Iron(ll) both colour and equation
green solution
[Fe(H2O)6]2+
what is the colour and equation of iron (ll) after addition of NaOH
green ppt
Fe(H2O)4(OH)2
[Fe(H2O)6] + 2NaOH —> Fe(H2O)4(OH)2 + 2H2O
what is the colour and equation of iron (ll) after addition of excess NaOH
no further change
what is the colour and equation of iron (ll) after addition of NH3
green ppt
Fe(H2O)4(OH)2
[Fe(H2O)6] + 2NH3 —> Fe(H2O)4(OH)2
what is the colour and equation of iron (ll) after addition of excess NH3
no further change
What is the colour and equation of iron(ll) after addition of Na2CO3
green ppt
FeCO3
[Fe(H2O)6] + CO3 2- —> FeCO3
