Test: Flame - JAMB MCQ

When sodium ions are subjected to a flame test, they emit a characteristic yellow flame. This yellow color is due to the electronic transitions of the electrons within the sodium atoms. These transitions involve the absorption and subsequent emission of energy in the visible light range, specifically in the yellow region.

The flame test is based on the principle that when metal ions are heated in a flame, they absorb energy and undergo electronic transitions. These transitions result in the emission of characteristic colors of light, which can be observed as a colored flame. Each metal ion emits a specific color due to its unique electronic configuration and energy level transitions.

Copper ions exhibit a characteristic green flame during a flame test. This green color is a result of the electronic transitions occurring within the copper atoms when they are excited by the heat of the flame. The energy absorbed by the copper ions is then released as green light.

Cleaning the wire loop between flame tests is crucial to prevent contamination and ensure accurate and consistent results. If the wire loop is not properly cleaned, residual metal ions from the previous test may remain and interfere with the subsequent flame test, leading to inaccurate observations. By cleaning the wire loop, any residual metal ions are removed, allowing for a fresh test with the new metal ion.

Potassium ions produce a brick-red flame during a flame test. The brick-red color is a result of the energy level transitions occurring within the potassium atoms when they are excited by the heat of the flame. This excitation leads to the emission of red light.

A borax bead is used as a flux in the flame test. A small amount of borax is heated in the flame until it melts and forms a glassy bead. When a metal ion is introduced to the borax bead, it dissolves into the molten borax, allowing for better observation of the characteristic flame color. The borax acts as a flux by lowering the melting point of the metal ions and facilitating their dissolution.

Strontium ions produce a violet flame during a flame test. The violet color is a result of the electronic transitions occurring within the strontium atoms when they are excited by the heat of the flame. The absorbed energy is released as violet light.

The color of the inner flame cone provides information about the temperature of the flame. Different metal ions have different flame colors, but the temperature of the flame can affect the intensity and appearance of those colors. By observing the inner flame cone, which is the hottest part of the flame, one can determine if the flame is at the optimal temperature for accurate observations.

Calcium ions produce an orange flame during a flame test. The orange color is a result of the electronic transitions occurring within the calcium atoms when they are excited by the heat of the flame. The absorbed energy is released as orange light.

The flame test can be used to identify unknown metal ions by comparing the observed flame colors with a reference chart or database of known flame colors for different metal ions. Each metal ion emits a unique flame color, allowing for the identification of the metal present based on the observed color.