chemistry

Question

A student wants to obtain pure water from a sample of sea water . Some white solid is found in the residue after the process is carried out for a long time .

To identify the elements inside the white solid , the student carries out flame test . Outline the procedures of the flame test and state the observable change(s) .

ENGLISH~

Answer 1

In carrying out a flame test, a nichrome (or platinum) wire is repeatedly heated in a non-luminous Bunsen flame and cleaned with concentrated hydrochloric acid until the wire imparts no colour to the flame. Dip the cleaned end of the wire into concentrated hydrochloric and stick a little of the powdered compound onto the wire. Put the compound into the cooler part of a non-luminous flame (blue flame) and observe the flame colour.

A bright yellow flame is observed.