bjerrum: Bjerrum plot

In seacarb: Seawater Carbonate Chemistry

Bjerrum plot

Description

Plot the concentration of the various ionic forms of a molecule as a function of pH

Usage

bjerrum(K1=K1(), K2=NULL, K3=NULL, phmin=2, phmax=12, by=0.1, conc=1, 
     type="l", col="black",  ylab="Relative concentration (%)", add=FALSE, ...)
     

Arguments

K1	First dissociation constant
K2	Second dissociation constant, default is NULL
K3	Third dissociation constant, default is NULL
phmin	Minimum pH value, default is 2
phmax	Maximum pH value, default is 12
by	Increment on the pH axis, default is 0.1
conc	concentration of molecule, default is 1
type	Type of plot, default is line
col	Color of plot, default is black
ylab	Label of Y axis, default is (mol/kg)
add	false:start new, true: add to current, default is false
...	Graphical parameters (see par) and any further arguments of plot, typically plot.default, may also be supplied as arguments to this function. Hence, the high-level graphics control arguments described under par and the arguments to title may be supplied to this function.

Details

Note that the concentration is plotted in mol/kg only if conc is given is mol/kg

Author(s)

Karline Soetaert [e-mail]

References

Zeebe, R. E. and Wolf-Gladrow D. A., 2001 CO2 in seawater: equilibrium, kinetics, isotopes. Amsterdam: Elsevier, 346 pp.

See Also

matplot, par, speciation.

Examples

## Plot the bjerrum plot for the carbonate system using the default values
bjerrum(K1(),K2(),main="DIC speciation",lwd=2) 
abline(v=-log10(K1()),col="grey")
mtext(side=3,at=-log10(K1()),"pK1")
abline(v=-log10(K2()),col="grey")
mtext(side=3,at=-log10(K2()),"pK2")
legend("left",lty=1:3,lwd=2,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for phosphate using the default values
bjerrum(K1p(),K2p(),K3p(),main="phosphate speciation",lwd=2)
legend("left",lty=1:4,lwd=2,legend=c(expression(H[3]~PO[4]),
	expression(H[2]~PO[4]^"-"),
expression(HPO[4]^"2-"),expression(PO[4]^"3-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of temperature
bjerrum(K1(T=25,S=35),K2(T=25,S=35),conc=1.3,main="effect of temperature" )
bjerrum(K1(T=0,S=35),K2(T=0,S=35),conc=1.3,add=TRUE,col="red")
legend("left",lty=1,col=c("black","red"),legend=c("T=25 oC","T=0 oC"))
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of salinity
bjerrum(K1(T=25,S=35),K2(T=25,S=35),conc=1.3,main="effect of salinity" )
bjerrum(K1(T=25,S=5),K2(T=25,S=5),conc=1.3,add=TRUE,col="blue")
legend("left",lty=1,col=c("black","blue"),legend=c("S=35","S=5"))
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of pressure
bjerrum(K1(P=0),K2(P=0),conc=1.3,main="effect of pressure" )
bjerrum(K1(P=300),K2(P=300),conc=1.3,add=TRUE,col="green")
legend("left",lty=1,col=c("black","green"),legend=c("P=0","P=300"),title="atm")
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

seacarb documentation built on May 31, 2023, 8:31 p.m.