My PBL Project

Introduction: Why do different elements emit different colors when exposed to a flame? A flame test is used in to identify certain metals and is based on the observation that each element emits light that gives a unique spectrum when passed through a spectroscope.

Materials:

• Bunsen burner

• Spray bottle

• Wire loop

• Barium nitrate

• Calcium nitrate

• Copper(II) chloride

• Lithium chloride

• Potassium nitrate

• Sodium chloride crystal

• Strontium nitrate

Procedure:

1. Take a wire loop and dip it in water.

2. Dip the wire loop into the bottle of metal.

3. Place the metal into flame and observe the flame.

Scientific principle/essential understanding:

• The scientific principle behind this experiment is that electrons release or absorb energy when they change energy levels. In this experiment, the energy released was observed. When an element is exposed to heat, the energy levels of one or more electrons might change. If the energy released after the changes in energy levels is in the form of visible light, the observer will be able to see a certain color, which is unique to each element.

Safety regulations:

• Keep flammable objects away from the bunsen burner.

• Wear goggles.

Title: Flame Test

Question

Write the question for investigation.

What is the color of a flame when the metal ions of Lithium, Sodium, Potassium, Calcium, Strontium. Barium, and Copper are exposed to the flame?

Design/Plan

Plan your investigation with your team. Show your notes and diagrams in the space below.

1. Use a wire loop to pick up a drop of solution.

2. Place drop into flame and observe the flame.

Investigation

Identify the purpose of your investigation and record it in the space below. Conduct your investigation . In the space provided, record - materials, experimental procedure, safety precautions, data, calculations, graph (if applicable), analysis, conclusions, and application/extension of learning. Be prepared to discuss your procedure and results with the group.

Purpose

Find the colors given off by metal ions when exposed to a flame

Materials

● Bunsen burner

● Spray bottle

● Wire loop

● Barium nitrate

● Calcium nitrate

● Copper(II) chloride

● Lithium chloride

● Potassium nitrate

● Sodium chloride crystal

● Strontium nitrate

Safety

Keep flammable objects away from the bunsen burner.

Wear goggles.

Data

Analysis and Conclusion

The color of a flame is unique for every metal ion; no color is the exact same. Lithium has a pink-red flame, sodium a yellow-orange flame, potassium a violet flame, calcium an orange-red flame, strontium a deep red flame, barium a green flame, and copper a blue-green flame.

Application and Extension

A flame test is used in to identify certain metals and is based on the observation that each element emits light that gives a unique spectrum when passed through a spectroscope. This can be used to identify the presence of metals in objects.