A sample of blood or tears has a pH of 7.40. What is the hydroxide-ion concentration of this solution?

1 Answer
Apr 27, 2018

#~~2.51*10^-7 \ "M"#

Explanation:

We first find the #pOH# concentration using the #"pH"# and #"pOH"# relationship equation:

#"pH + pOH"=14#

#:."pOH"=14-"pH"#

#=14-7.4#

#=6.6#

Now, we can find the hydroxide ion concentration using the #"pOH"# equation:

#"pOH"=-log[OH^-]#

  • #[OH^-]# is the hydroxide ion concentration in terms of molarity

And so, we get:

#-log[OH^-]=6.6#

#[OH^-]=10^-6.6 \ "M"#

#~~2.51*10^-7 \ "M"#