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sankofa1814
01-23-2012, 10:53 AM
Hello

I am new to this forum and I know how to make a ppm solution but I dont know how to break it down into other ppb solutions.

example.. if I have a solution of 1 ppm of lead , how do I make separate solutions of 5, 10, 15, and 20 ppb from the 1ppm solution

JohnS
01-23-2012, 11:06 AM
Hello

I am new to this forum and I know how to make a ppm solution but I dont know how to break it down into other ppb solutions.

example.. if I have a solution of 1 ppm of lead , how do I make separate solutions of 5, 10, 15, and 20 ppb from the 1ppm solution

1 ppm = 1000 ppb, so to make
5, 10, 15, 20 ppb, take any convenient volume and dilute to
200X, 100X, 66.67X, and 50X that initial volume, respectively

That "convenient volume" must be measurable, and, when diluted, provide a little more working solution than you need.

sankofa1814
01-23-2012, 11:11 AM
1 ppm = 1000 ppb, so to make
5, 10, 15, 20 ppb, take any convenient volume and dilute to
200X, 100X, 66.67X, and 50X that initial volume, respectively

That "convenient volume" must be measurable, and, when diluted, provide a little more working solution than you need.

sorry, still kinda confused ....so if I would like to make 50ml solutions of each ppb standard from the initial 1ppm solution how would that work?

Mrs X
01-23-2012, 12:07 PM
sorry, still kinda confused ....so if I would like to make 50ml solutions of each ppb standard from the initial 1ppm solution how would that work?

1ppm is 1000ppb, so make 100mL of 100ppb (10mL of 1ppm diluted to 100mL in a volumetric flask at 20°C)

For 50mL of 5ppb, take 5/100 x 50mL = 2.5mL of the 100ppb solution and dilute it to 50mL in a volumetric flask (at 20°C)

for 50mL of 10ppb, take 10/100 x 50 = 5mL of the 100ppb solution and dilute it to 50mL in a volumetric flask (at 20°C)

Have a go at the other two, and post back here to make sure you understand it if you like. :)

sankofa1814
01-23-2012, 12:35 PM
1ppm is 1000ppb, so make 100mL of 100ppb (10mL of 1ppm diluted to 100mL in a volumetric flask at 20°C)

For 50mL of 5ppb, take 5/100 x 50mL = 2.5mL of the 100ppb solution and dilute it to 50mL in a volumetric flask (at 20°C)

for 50mL of 10ppb, take 10/100 x 50 = 5mL of the 100ppb solution and dilute it to 50mL in a volumetric flask (at 20°C)

Have a go at the other two, and post back here to make sure you understand it if you like. :)

Ok, so I think I understand, once I have the 100 ppb solution all I have to do it take away the respective amounts of the 100 ppb solution (2.5 mL, 5mL, 7.5 mL, and 10mL) and bring the volume to 50 mL? I am using H. CNO3 would room temperature be ok?

thanx