Microscopic World 1 Flashcards
why argon is stable?
it has a stable octet structure
definition of isotopes
atoms of the same element with same number of protons but different numbers of neutrons
why F3BNH3 has a dative covalent bond
BF3 has a vacant site to accept lone pair electrons to obtain stable octet
or(2017)
hv lone pair electrons
other molecules doesn’t have electrons in outermost shell
dative bond formed between X and Y by sharing electron pair
what is metallic bond
electrostatic attraction between metal cation and sea of delocalized electrons
explain boiling point high or low
XXX use structure to explain
RMB to use bonding to explain!!
why inverted funnel is used when ammonia is transferred to a beaker
prevent sucking back as NH3 is very soluble in water
2012q7
describe the bond formation between BF3 and NH3
In BF3, there are three bonding electrons and a vacant site in the outermost shell of the B atom
By accepting the lone pair electrons from N atom of NH3 and form a dative covalent bond with N, the B atom attains the stable electronic configuration of a noble gas.
why atoms in same group reacts similarly
they have the same number of outermost shell electrons so they have similar chemical properties
XX same chemical properties
why filter paper are soaked with ionic compound instead of water
to increase the electrical conductivity of the filter paper
heating hydrated copper sulphate to dryness
physical or chemical change?
physical
no new chemical product forms
what is octet rule
all atoms tend to attain the stable electronic configuration of a noble gas by sharing or transferring electrons
all elements in Group 0 exist in gaseous state in room temperature and pressure
T/F
T
even Rn has a boiling point of -62oC
why deuterium reacts with oxygen in the same way as hydrogen
H and D have the same electronic configuration
isotopes have the same chemical properties
what will be observed on the surface on the metal after some time
the metal surface will turn dull
why carbon dioxide can be used in fire fighting
CO2 is denser than air
so it can exclude the air from the fuel
