Fichas
Transition Metals
Fichas del conjunto (22)
- 1What are transition metals?A d-block element that forms an ion with an incomplete d sub-shell.
- 2Why are scandium and zinc not transition metals?Scandium has a completely empty sub shell and zinc has a completely full d sub shell. The d sub shell must be incomplete for it to be a transition metal.
- 3How do you write electron configurations for elements and ions?
- 4Why do chromium and copper not follow the electron configuration pattern?Electron repulsion in the outer electrons are minimised resulting in increased stability of the atoms.
- 5What is the electron configuration of chromium?1s2 2s2 2p6 3s2 3p6 4s2 3d5
- 6What is the electron configuration of copper?1s2 2s2 2p6 3s2 3p6 4s1 3d10
- 7What happens to a transition element in a reaction?They lose electrons to form positive ions; losing their 4s electrons before their 3d electrons.
- 8Why are 4s electrons lost first?They have a higher energy.
- 9What is the difference between a d block element and a transition element?Transition elements are elements where the d orbital is incomplete whereas d block elements have a d orbital as the highest energy and this can be empty or full.
- 10Write the electron configuration for: Cr, Mn2+, Sc3+ and Ti1s2 2s2 2p6 3s2 3p6 4s2 3d5
1s2 2s2 2p6 3s2 3p6 3d5
1s2 2s2 2p6 3s2 3p6
1s2 2s2 2p6 3s2 3p6 4s2 3d2 - 11Physical properties of transition metals.Shiny in appearance
High densities
High melting points
High boiling points - 12What do transition metals exist as when they are solids?Giant metallic lattices, containing delocalsised electrons which can move to conduct electricity.
- 13Uses of transition metalsCoins
Joint replacements
Telephone boxes
Alloyed for use in construction - 14Transition elements from titanium to copper can form ions with how many oxidation states?Two or more
- 15Why do transition metals form compounds with ions in the +2 oxidation state?As they lose the 2 electrons from the 4s orbital. (Higher energy level than that of 3d orbital, although close together)
- 16Why are compounds containing transition metal ions coloured?Some of the wavelengths of visible light are absorbed. The colour is a combination of the wavelengths that have not be absorbed.
- 17What is a catalyst?A substance that increases the rate of a reaction by providing an alternative route with a lower activation energy.
- 18Why are transition metals good catalysts?They provide a surface on which a reaction can take place.
Transition metal ions have the ability to change oxidation states by gaining or losing electrons. They then bind to reactants forming intermediates as part of a chemical pathway with a lower activation energy. - 19Haber ProcessN2(g) + 3H2(g) <=> 2NH3(g)
Iron metal is the catalyst - 20Contact Process2 SO2(g) + O2(g) ⇌ 2 SO3(g)
Vandium Oxide catalyst, V2O5 - V has the 5+ oxidation state - 21Hydrogenation of AlkenesUnsaturated compounds to saturated compounds.
Nickel catalyst, lowers the temperature and pressure. - 22Decomposition of hydrogen peroxide.2H2O2 ---> 2H20 + O2
Manganese oxide is the catalyst with +4 oxidation state.
Información
- Descripción
- OCR A2 Chemistry - F325, Transition Elements
- Creado por
- Madeleine.Dc
- Visitas
- 731
- Etiquetas
- Valoración