Topic 4: Inorganic Chemistry & Periodic Table Flashcards
What are the physical properties that follow trends down the group?
- Ionisation Energy
- Reactivity
- Atomic Radii
How does the Ionisation Energy of a Group 2 Metal change as you go down the group?
The First Ionisation Energy decreases down group 2.
This is due to:
- Increased Shielding
- Increased Atomic Radii
Therefore:
- The outer electrons are easier to lose
How does the Atomic Radii of a Group 2 Metal change as you go down the group?
The Atomic Radii increases down group 2.
This is due to:
- Additional Electron Shells
How does the Reactivity of a Group 2 Metal change as you go down the group?
The Reactivity increases down group 2.
This is due to:
- Increased Shielding
- Increased Atomic Radii
Therefore:
- The outer electrons are easier to lose
What do Group 2 Elements and Compounds react with?
Group 2 Elements:
- Metal + Water
- Metal + Chlorine
- Metal + Oxygen
- Metal + Dilute Acids
Group 2 Compounds:
- Metal Hydroxides + Dilute Acid
Describe what happens when a Group 2 Metal reacts with Water.
Water:
The Group 2 Metals react with H20(l) in a redox reaction to form X(OH)2 + H2
X(OH)2 forms an alkaline solution hence why group 2 metals are known as the “Alkaline Earth Metals”
Steam:
The Group 2 Metals react with H20(g) in a redox reaction to form XO + H2
This reaction is much faster since there is extra energy (steam).
The metal burns with a white bright flame to form H2 and XO - a white powder.
What is the reaction between a Group 2 Metal and Water?
Liquid Water:
X + 2H2O –> X(OH)2 + H2
Steam:
X + H20 –> XO + H2
Describe what happens when a Group 2 Metal reacts with Chlorine.
Group 2 Metals react with Cl2(g) to form metal chlorides, which are all white precipitates.
The reactions become more vigorous as you go down the group because reactivity increases down Group 2.
What is the reaction between a Group 2 Metal and Chlorine?
X + Cl2(g) –> XCl2
Describe what happens when a Group 2 Metal reacts with Oxygen.
Group 2 Metals react with O2(g) to form oxides.
Once Initiated the reaction is vigorous.
Sr and Ba can react with excess O2 and heat energy to form metal peroxides.
What is the reaction between a Group 2 Metal and Oxygen?
Most Group 2 Metals:
2X + O2 –> 2XO
Sr and Ba:
X + O2 –> XO2
Describe what happens when a Group 2 Metal reacts with a Dilute Acid.
The Group 2 Metals react with dilute acids to produce bubbles of H2(g) and solutions of metal compounds.
What are the reactions between Group 2 Metals and Dilute Acids?
HCl:
X + 2HCl –> XCl2 + H2
H2SO4:
X + H2SO4 –> XSO4 + H2
HNO3:
X + 2HNO3 –> X(NO3)2 + H2
Describe what happens when a Group 2 Metal Hydroxide reacts with a Dilute Acid.
The Group 2 Hydroxides react with Dilute Acids to form a Salt and Water.
This is a type of neutralisation reaction.
The salt formed depends on the acid used.
What is the reaction between a Group 2 Metal Hydroxide and Dilute Acid?
HCl:
X(OH)2 + 2HCl –> XCl2 + 2H2O
H2SO4:
X(OH)2 + H2SO4 –> XSO4 + 2H2O
HNO3:
X(OH)2 + 2HNO3 –> X(NO3)2 + 2H2O
