Chemistry

Alchemy

Before the scientific method, alchemists studied substances in the quest to convert lead into gold.  However, alchemists had no understanding of the atomic nature of matter — instead, they believed in secretive mystical properties that they tried hiding from each other.

The Scientific Method

Unlike the secretive and mystical approaches of alchemy, modern chemistry is built upon observing our world, making hypotheses, and then experimenting to determine the nature of reality.

From this video, you should learn the six steps of the scientific method and how it can be applied to answering everyday questions.

The Phases Around Us

Every day, you directly observe three major phases of matter:

• Gasses like the air we breathe.

• Liquids like the water we drink.

• Solids like the floor beneath our feet.

Temperature Extremes and the Phases of Matter

The surface of the Earth is a relatively constant temperature — you might see water transition from ice to liquid to vapor on a hot summer day, but you don't need to worry about your plastic cup boiling away under the sun's heat.  At more extreme temperatures and pressures, you can see additional states of matter such as supercritical fluids, plasmas, condensates, and others.  These extreme states can have important applications in superconductors, computing, aviation, and other areas.

Physical Properties of Matter

Matter has two main types of properties:

• Physical Properties you can observe from the material itself.

• Chemical Properties that affect how the material changes when it reacts with other substances.

Measuring Quantities

The correct measurement of quantities such as mass, volume, and temperature is crucial for conducting experiments and manufacturing materials.

Measurement has two key concepts you must bear in mind:

• Accuracy describes whether your measurement matches reality.

• Precision describes whether your measurement matches other measurements, even if those numbers don't match reality.

A reliable measurement needs to be both accurate and precise, and the true test of an experimental measurement is whether it can be repeated by other researchers.

Experiments with Pennies

Physical Properties of Pennies

• Investigating the Physical Properties of US Penny | Chemvision

• Density of a Penny | Brooklin Technical High Schooly

Water Drop Experiment

• Penny Drop Lab | Licking Heights Schools

• Drops on a Penny | Steve Spangler

• Repeat using water with added detergent