chem general Flashcards
define catalyst
material that increases reaction rate
why does acid rain react slowly with metals and with limestone
low concentration of acid/ small surface area
: so collision frequency is low
why molecules are much less reactive than atoms
molecules have strong covalent bonding between atoms // atom has high tendency to gain electrons / has incomplete electron shell
difference between ionic bonds and covalent bonds
ionic = between metallic and non-metallic elements
covalent = between non-metallic elements
why does ionic compounds have high melting point
attractive force between oppositely charged IONS // more energy required to overcome force
how protons (H+) are involved in reaciton between an acid and a base
protons transferred from acid to base
define activation energy
minimum energy for particles/reactants to react
define homologous series
same general formula // similar chemical properties
energy transfers involved in generating electrical energy from diesel fuel
chemical -> thermal // thermal -> kinetic // kinetic -> electrical
in haber process, which substance is removed from air when hydrogen burns
oxygen
in haber process, what is the purpose of iron in the reaction vessel
catalyst // speeds up reaction // lowers activation energy
how atoms are formed at the anode
__ ion s are oxidised/lose electrons
why are reactions faster at higher temp
particles have more KE // greater collision frequency // more particles have activation energy to react
electrolysis - why chlorine gas is made at the anode
chloride IONS are attracted to the anode // chloride IONS are negative
electron loss occurs at the anode // chlorine atoms combine to form chlorine molecules
why is copper a conductor of electricity
metallic bonding // has sea of electrons // which can move through the structure
