SoME BASIC (ONCEPT$ oF CHENISTRY
MEASUREMENT AND SI G FICANT FIGyURES
AccURACY accuag s a measune of the defference bel weat
the ezperime htel Value mean valu o4a
set ef measurement& cmd
How Close
tle tee value.
PRECIsION precisi u expresed as tha dtlerence beteen
valee
c measyredl vale ormd te gnthietic mean
Semes me asuyemedsa Closeisd o
txponenia Nmber oy ceientif Notao
In geneyal, in
be
Seienti4ic
Seien titic notctien,
notctien a number mey
ec pressel as!
n
ushone am exponent haing ve oy
valus
-we
m
single nn-2eo digit omd
ies befween 1 to lo
Ncalled di git term md
is callcl exponent
Nnber h aa singk
mm oj
Auwbey o plaes decimal
polnt was moveel
n
N
Moved t
moved ight
Sl6NI Fl CA NT FlGURE wes
Sig nificant 4ig in a
Nymber ae clL he certain digits plus o unertasn
digit. hus
the number o Significqt fi9ures Con veys
ngemalion Hal the Jast digit, dl oter
dd gi to ae Knousn with tataunty Sigeicanf Ayu a
e
LÄWS oF CHE MCAL COMBINATION
Dusing
Law
ony
ot (onvservaon ot
physical or
M aas
chmi Cal
! change, He totul Ha
Hie
Guacteuts"
, Cu.
Co
bt
A
law
es odified
Nass-
, tte
ehergy
Modifiecd
s ich
dao
stae -
s Knowh as
•f CornAervation of
intercon vertible. but the tofal
Mass am ehergy ate
Stumm o} mass comd ehergy he stem remans (notant
(2) Law proprtions er Law of constunt
f definite
proportion
Law of Constant Comp0itiorn 4tatis that
A pure chemical Compound alway Contain s9m olemaud
Ccmbinl togeter in He bgmme lefinite propution by
weight Jo eg o2 2gc t 327
(3) Lauo of multiple proburtions
Law miltpl propirton stts that
of
(t two elemets (omblne to ferm
lohen
foo Compounds, then a msses oA Cns o
tD ha
oY
el
more
emds
ha
shich Combine with a ixecl mas8 of He otHher, beas a sim
ohole mymbey rato)
Ex: + welis
Dxygon
Coz 23 |89
dud
Co
yhoyen Hyoogan peroaicl
329 349.
he masss 'onygon I39 ( 32) which Combin with fseeol
Mass of hyosogan (2 part) bear a simble aatio be; le:
(4) Gray LiusIac's lus of Comblming volumes
bray Lwss9c's law sf Combining volumo state t.
( ondler imilay (ondi ton of tenh md presure, when
gases eact ogee?y He volums of ho eactng gases as
products Ci/ gases) bear e simhle whele numbe
Matio
Ex!
| 2H/a)
rhe
|3
vol
::2.
tatio
vol
af Hyrogen
2 vul:
chloide ' Hydrogen chlori
MEASUREMENT AND SI G FICANT FIGyURES
AccURACY accuag s a measune of the defference bel weat
the ezperime htel Value mean valu o4a
set ef measurement& cmd
How Close
tle tee value.
PRECIsION precisi u expresed as tha dtlerence beteen
valee
c measyredl vale ormd te gnthietic mean
Semes me asuyemedsa Closeisd o
txponenia Nmber oy ceientif Notao
In geneyal, in
be
Seienti4ic
Seien titic notctien,
notctien a number mey
ec pressel as!
n
ushone am exponent haing ve oy
valus
-we
m
single nn-2eo digit omd
ies befween 1 to lo
Ncalled di git term md
is callcl exponent
Nnber h aa singk
mm oj
Auwbey o plaes decimal
polnt was moveel
n
N
Moved t
moved ight
Sl6NI Fl CA NT FlGURE wes
Sig nificant 4ig in a
Nymber ae clL he certain digits plus o unertasn
digit. hus
the number o Significqt fi9ures Con veys
ngemalion Hal the Jast digit, dl oter
dd gi to ae Knousn with tataunty Sigeicanf Ayu a
e
LÄWS oF CHE MCAL COMBINATION
Dusing
Law
ony
ot (onvservaon ot
physical or
M aas
chmi Cal
! change, He totul Ha
Hie
Guacteuts"
, Cu.
Co
bt
A
law
es odified
Nass-
, tte
ehergy
Modifiecd
s ich
dao
stae -
s Knowh as
•f CornAervation of
intercon vertible. but the tofal
Mass am ehergy ate
Stumm o} mass comd ehergy he stem remans (notant
(2) Law proprtions er Law of constunt
f definite
proportion
Law of Constant Comp0itiorn 4tatis that
A pure chemical Compound alway Contain s9m olemaud
Ccmbinl togeter in He bgmme lefinite propution by
weight Jo eg o2 2gc t 327
(3) Lauo of multiple proburtions
Law miltpl propirton stts that
of
(t two elemets (omblne to ferm
lohen
foo Compounds, then a msses oA Cns o
tD ha
oY
el
more
emds
ha
shich Combine with a ixecl mas8 of He otHher, beas a sim
ohole mymbey rato)
Ex: + welis
Dxygon
Coz 23 |89
dud
Co
yhoyen Hyoogan peroaicl
329 349.
he masss 'onygon I39 ( 32) which Combin with fseeol
Mass of hyosogan (2 part) bear a simble aatio be; le:
(4) Gray LiusIac's lus of Comblming volumes
bray Lwss9c's law sf Combining volumo state t.
( ondler imilay (ondi ton of tenh md presure, when
gases eact ogee?y He volums of ho eactng gases as
products Ci/ gases) bear e simhle whele numbe
Matio
Ex!
| 2H/a)
rhe
|3
vol
::2.
tatio
vol
af Hyrogen
2 vul:
chloide ' Hydrogen chlori
