What is the maximum number of electrons found in an atomic orbital? The graph shows the first five ionisation energies for sodium, aluminium and magnesium - HSC - SSCE Chemistry - Question 33 - 2003 - Paper 1

The ionisation energy graph provides insights into the arrangement of electrons in sodium, aluminium, and magnesium. As electrons are removed, the ionisation energy often increases due to the greater positive charge experienced by remaining electrons after each successive removal. The large jump in ionisation energy between the removal of certain electrons indicates a change in the electron shell structure, suggesting that the removed electron was in a higher energy level. For instance, sodium shows a significant increase in ionisation energy after the removal of one electron, indicating the subsequent electron is closer to the nucleus. By analyzing these trends across the elements, we can infer the electronic configuration and determine the valence electrons, which are crucial for understanding chemical reactivity.

During the investigation of flame colours in metals, several precautions were taken to ensure safety and accuracy:

1. Safety Gear: I wore safety goggles and lab coats to protect against splashes and heat.
2. Proper Ventilation: The experiment was conducted under a fume hood to avoid inhaling any harmful fumes released during the investigation.
3. Handling Chemicals: I handled all metal salts with care, using gloves to prevent skin contact.
4. Equipment Check: All equipment was checked for damage or defects before use to ensure it was safe for the experiment.

The procedure for observing flame colours involved the following steps:

1. Preparation of Samples: Small quantities of different metal salts were prepared on a clean, dry wooden splint.
2. Ignition: Each splint was then placed in a clean Bunsen burner flame one at a time.
3. Observation: The flame colour produced by each metal ion was observed and noted. I made sure to keep a consistent distance from the flame for accurate observation.
4. Recording Results: After each observation, I recorded the flame colour associated with each type of metal ion tested.

The relationship between the chemical composition of pigments and their properties lies in the nature of the materials used. Traditional Aboriginal pigments often derive from natural sources like ochre, which contains iron oxides. The varying oxidation states of iron can produce different shades of red, yellow, and brown.

1. Chemical Composition: Natural pigments are primarily composed of earth materials, such as hematite (Fe2O3) for red and goethite (FeO(OH)) for yellow. The specific minerals present not only affect the colour but also the opacity and texture of the pigment.

2. Properties: The chemical stability of these pigments allows them to resist fading when exposed to light and air, making them ideal for long-lasting artworks. Additionally, the particle size affects the pigment's ability to adhere to surfaces and mix with binders, impacting the application techniques used by artists.

In summary, the interplay between chemical structure and physical properties is crucial in determining the performance and aesthetic qualities of pigments in Aboriginal art.