the study of the compostion of matter and the changes that matter undergoes

Because living and nonliving things are made of matter, chemistry affects all aspects of life and most natural events. 

area of study that focuses on the composition of matter

-measuring the level of lead in drinking water

firm.

A chemist is likely to be working in more than one area of chemistry to determine the composition of an organic chemical.

Research that is directed toward a practical goal or application.

In practice, pure chemistry and applied chemistry are often linked.

Pure chemistry; Hermann Staudinger, a  German chemist, proposed that these materials contained small units joined together like links in a chain.

By 1950, some doctors began to recommend a low daily dose or aspirin for patients who were at risk for a heart attack. Many heart attacks occur when blood clots block the flow of blood through arteries in the heart. Some researcher suspected that aspirin could keep blood clots from forming.

one of the easiest ways to conserve energy is through the use of insulation. Insulation acts as a barrier to heat flow from the inside to the outside of a house or from the outside to the inside of a freezer.

There are over 2000 prescription drugs. They are designed to treat various conditions including infections, high blood pressures, and depression.

Many drugs are effective because they interact in a specific way with chemicals in cells.

Chemistry can supply materials to repair or replace body parats. Diseased arteries can be replaced with plastic tubes.

Some factors that decrease producitivity are poor soil quality, lack of water, weeds, plant disease, and pests tha teat crops. Chemists can help with many of these problems.

Chemists can also help to conserve water.

Farmers have used chemicals to attack insect pests. In that past, these chemicals were nonspecific; that is, a chemical designed to kill a pest could also kill useful insects.

Alchemy arose independently in many regions of the world. Alchemy had a practical side and a mysical side.

Practical alchemy focused on developing techniques for workign with metals, glass, and dyes.

for working with chemicals.

Alchemists developedprocesses for separating meixtures and purifying chemicals.

When scientists collaborate and communicate, they increase the likelihood of a successful outcome

1. Analyze- to solve a word problem, you must first determine where you are starting from (identify what is known) and where you are going (identify the unknown) to be a number, you need to determine what units the answer should have before you do any calculations.
   
2. Calculate- if you make an effective plan, doing the calculations is usually the easiest part of the process.
   
3. Evaluate-after you calculate an answer, you should evaluate it.