introduction to transition metals Flashcards
why are Sc - Zn categorised as d block elements?
they have their highest energy electrons in a d sub shell/orbital
give 3 typical properties of d block elements
- high mp/bp
- shiny
- good conductors of heat & electricity
- malleable
- ductile
what are common uses of iron?
- construction
- tool production
what are common uses of copper?
- electrical cables
- water pipes
what are common uses of titanium?
- aerospace industry
- medical applications such as joint replacements
why do copper and chromium not follow the normal pattern of filling 4s before 3d?
a half filled d5 sub shell and full d10 sub shell give additional stability to the atoms
which electrons are lost first when d block elements form ions?
4s
define ‘transition metal’
a d block element which forms at least 1 ion with a partially filled d sub shell
why are Sc and Zn not transition metals?
Sc only forms 3+ ion which has an empty d subshell
Zn only forms 2+ ion which has a full d subshell
- transition elements must have a partially filled d sub shell
state the 3 properties of transition metals that other metals do not have?
- variable oxidation states
- coloured compounds
- compounds and elements can act as catalysts
what colour is potassium dichromate?
bright orange
what colour is cobalt II chloride?
purple pink
what colour is nickel II sulphate?
green
what does colour of transition element compounds vary with?
oxidation number
what is the catalyst in the Haber process?
Fe
what is the catalyst in the contact process?
V2O5
what is the catalyst in catalytic decomposition of hydrogen peroxide?
MnO2
what is a homogenous catalyst?
catalyst and reactants are in same physical state
what is a heterogenous catalyst?
catalyst is in different physical state to reactants
why do Zn compounds dissolve to form a colourless solution?
- colour is associated with presence of a partially filled d orbital
- Zn only forms Zn2+ ions
- Zn2+ ions have a full d sub shell
