Unit Conversion Charts for the Analytical Chemist

Dr. Deepak

 

Chemical analysis measurements

An analytical chemist needs to express analytical data in units which may require conversion to other units for ease of calculation and communication of results. Most modern analytical techniques are capable of expressing results in different units at the push of a button but a basic understanding of inter-conversions and factors involved is essential to gain confidence on results that you communicate.

Measurement units commonly used in analytical work introduced you to the common units that you come across while doing your routine analysis. However, it would be a big help if you have ready access to the interconversion charts. In the present article simple interconversion charts are presented on units that you are likely to come across during routine laboratory activities.

Length
From	To	Conversion Factor
cm	mm	10
cm	m	10-1
m	cm	102
mm	µm	103
µm	mm	10-3

Time
From	To	Conversion factor
sec	m sec	103
sec	µsec	106
sec	nano sec	109
sec	Pico sec	1012
m sec	sec	10-3
µ sec	sec	10-6
nanosec	sec	10-9
pico sec	sec	10-12

Mass
From	To	Conversion Fcator
gm	mg	103
gm	µg	106
gm	ηg	109
gm	pg	1012
mg	gm	10-3
µg	gm	10-6
ηg	gm	10-9
pg	gm	10-12

Volume
From	To	Conversion Factor
lit	ml	103
lit	µl	106
ml	lit	10-3
ml	µl	103
µl	ml	10-3
µl	lit	106

Temperature
From	To	Conversion Factor
OC	OF	(OC-32)x 5/9
OF	OC	(OCx9/5)+32
OC	OK	OC+273.15

Heat
From	To	Conversion Factor
calories	milli calories	103
calories	joules	4.184
joules	calories	0.239

Electrical Units
From	To	Conversion Factor
amperes	milliamperes	103
milli amperes	amperes	10-3
amperes	micro amperes	106
micro amperes	amperes	10-6
volts	millivolts	103
volts	microvolts	106

Concentration
From	To	Conversion Factor
moles	millimoles	X103
millimoles	moles	X10-3
ppm (mg/l)	ppb(µg/l)	X103
ppm (mg/l)	ppt (ηg/l)	X106
ppb	ppm	X10-3
ppt	ppm	X10-6

Pressure
From	To	Conversion Factor
bar	pascal	105
bar	psi	14.50
pascal	torr	0.0075
torr	pascal	133.32
mm of Hg	atmosphere	0.00132
mm of Hg	pascal	133.32
mm of Hg	torr	1
psi	bar	0.0689
psi	pascal	6894.75
psi	torr	51.72
psi	mm of Hg	51.72

Wavelength
From	To	Conversion Factor
meters	µm	106
µm	meters	10-6
cm	µm	104
µm	cm	10-4
λ µm	wavenumber (cm-1)	104/ λ (m µ)
wavenumber (cm-1)	λ µm	104/ / λ (cm-1 )

The charts would serve as a ready reference and will save your valuable time spent otherwise searching for conversion factors. Hopefully the information would prove to be useful.