TEACHER: MS. TAHIRA A.AZIZ SUBJECT: SCIENCE TEACHER: MS. TAHIRA A.AZIZ GRADE: VIII A

Flame Test Metals change the colour of a flame when they are heated in it. Different metals give different colours to the flame, so flame tests can be used to identify the presence of a particular metal in a sample. This is how students carried out a typical flame test.

Learning Goals Students will: 1.develop skills in careful qualitative observations and recording experimental data. 2.understand the relationship between color emitted by atoms of metal compounds and their electron structure. 3.use color emitted by metal atoms in a flame to identify the metal in an unknown salt compound. Time: 2 periods (40 min each)

Description The lab will be conducted after the introduction of the Metals of the Periodic table in a classroom. Students will conduct flame tests on a number of unknown salt compounds. This is lab activity used during the unit on the Periodic Table. The activity took 60 - 80 minutes. Students had experience with a Bunsen burner and basic lab safety.

Classroom discussion

Student presentation

Student explanation

Apparatus and materials used Bunsen burner Watch glass dish Platinum wire Beaker Salts Hydrochloric acid solution, (dilute)

Classic Wire Loop Method: First, you need a clean wire loop. Nickel-chromium loops are most common. They may be cleaned by dipping in dilute hydrochloric acid, followed by rinsing with distilled water. The loop must be cleaned between tests. The clean loop is dipped in a powder of an ionic (metal) salt. The loop with sample is placed in the clear or blue part of the flame and the resulting color is observed.

Start of experiment: