Chemistry: A Blend of Science and Technology * Scientists develop models, conduct experiments and seek patterns * They work on discoveries of other scientists from before * Chemical techniques and processes were invented by early chemists (making medicines, growing crops, shaping metals, glassware, distillation)
Chemistry, Technology, Society, and the Environment * STSE- science, technology, society and the environment and their interactions
STSE issue: Are Phosphates Helpful or Harmful? * Phosphates promote plant growth, used in food additives, medicines, dishwasher and laundry detergent * Found in bones and teeth and excreted as waste from the body
Phosphates Causing Trouble * Lake Erie has large amount of algae on the surface since phosphate went into the water * Unpleasant odour, fish were dying as algae use up the oxygen * Caused by wastewater containing detergents, sewage and run-off from farms with fertilizers * Amount of phosphate in products when down by 90%
1.2- Describing and Measuring Matter * Matter- anything that has mass and volume
Describing matter * Properties- characteristics that help describe and identify matter * Chart on page 12 * Physical property- a property that you can observe without changing one kind of matter into something new * Chemical property- a property that you can observe when one kind of matter is converted into a different kind of matter * Qualitative- describe them in words, but can’t measure or express them numerically * Quantitative- measured and expressed numerically
Using measurements to describe matter * International system of units (SI) allows scientists over the world to rely on a standard system of measurement * Chart (7 base SI units)