Question

Describe some advantages ICP has over other elemental analysis method.

What is the cause of signal interference and how can interference be dealt with?

What is a plasma? Where can plasma be found naturally?

Many ICP instruments can measure emission radially and axially (ours cannot measure both simultaneously). Explain what this means and describe the usefulness of each.Why is pure water called 18 MΩ water?

Answer 1

Describe some advantages ICP has over other elemental analysis method. Answer ICP is a inductively coupled plasma mass spectroscopy (ICP-MS) technique which is used to determine concentrations elements (low or ultra low). Atomic elements are lead through a plasma source where they become ionized and then, these ions are sorted on account of their mass. The advantages of the ICP-MS technique over other elemental analysis like AAS (Atomic Absorption Spectroscopy)are: .ICP has extremely low detection limits .ICP has a large linear range In ICP there is the possibilities to detect isotope composition of elements Disadvantages of the ICP-MS detection are that there is a spectral and non-spectral interference and also they are expensive. They are sensitive towards light. What is the cause of signal interference and how can interference be dealt with? Answer: Mainly there are two types of interferences ICP-MS that is isobaric and polyatomic. In the isobaric interferences different elements whose isotopes share a common mass interfere themselves. In polyatomic case interferences result from the combination of two or more similar isotopes from the different elements. To deal with interference we should do the following use high resolution ICP-MS. Matrix alteration through elimination .The use of collision cells to destroy molecular interfering ions .Use the Cool plasma to reduce background interferences use alternate ICP discharges (He, mixed gas (He-Ar, N2-Ar, ) .Use Low-Pressure ICP discharges