Chapter 8 - Reactivity Trends Flashcards
Group 2, The halogens and Quantitative analysis.
What is a reducing agent?
A species that donates it’s electrons to another species, thereby reducing that species.
Which group are reducing agents commonly found?
Group 2
(Be, Mg, Ca, St, Br)
What is the trend in reactivity down group 2?
Reactivity increases. (This is because the further away an electron is from the nucleus)
Explain the trend of reactivity down group 2
Increased atomic radius and shielding effect so ionisation energies decrease. Therefore it’s easier to lose electrons.
What are the products of a group 2 element reacting with water? metal + water = ?
metal + water = Metal hydroxide and hydrogen
What is the product of a group 2 element reacting with oxygen? metal + oxygen = ?
metal + oxygen = Metal oxide
group 2 metal oxide + water = ?
group 2 oxide + water = metal hydroxide
What is the trend of solubility down group 2?
Increases
Explain the trend of solubility down group 2
Down the group, the solution has a greater concentration of OH-.
Given that group 2 oxides, hydroxides and carbonates neutralise acids, what can they be referred to as?
Bases
Given that most group 2 oxides, hydroxides and carbonates are soluble in water, what are they also besides bases?
Alkalis
What is the use of calcium hydroxide in agriculture?
Increases the pH of acidic soils.
Ca(OH)(2) + 2H+ -> Ca2+ + 2H(2)O
How are group 2 compounds used in medicine?
Used in indigestion tablets as antacids, often a suspension of a metal hydroxide in water.
What is another name for group 2?
Alkaline Earth Metals
What is another name for group 7?
Halogens