Sometimes chemical changes are able to bring energy into the system.

More chemical and use information is also available on this site.

I know a bit about the chemical basis of life.

But if it changes color that is evidence of a chemical change.

We know, for example, that he has used chemical weapons on his own people.

Sort of where it's coming from, so we've got chemical energy.

It does give off heat, so there is evidence of chemical change.

For example, we can change chemical process fast and easily.

In the past, Iraq used chemical weapons to kill people.

But chemical companies will not be required to act until July.

When more chemical data became available some groups were split.

But the risks are too great to leave chemical security in private hands.

Light can have a lot of energy and is able to break chemical bonds.

But I've run up against a rather difficult problem which is more chemical than biological.

"We'd rather not in many cases, but this is one of the things we would like chemical companies to be responsible for."

In chemical country, product names are not always what they seem.

A chemical change took place, and lucky for us it did.

In the case of burning, there is a chemical change.

He was the author of several books on chemical subjects.

She said a chemical study was under way to determine the type of drug he used.

"These chemical things have a bad impact on human bodies."

Tomorrow I would find chemical solutions to these new problems.

Absorption is a process that may be chemical or physical.

So far no biological or chemical weapons have been found in Iraq.

Food and chemical companies are expected to oppose it in court.

There are some chemical substances that no one should ever make.

She had no doubt he knew all about chemical substances.

This need not be a chemical substance at all in the ordinary sense of the word.

Chemical substances or techniques are used for body care, food and health products.

We also have an even higher number of sites where work is carried out using chemical substances.

The women's tears have a chemical substance which is able to improve health.

Could it be due to some chemical substance in the steam?

In other cases it is referred to as an "unidentified chemical substance".

Have the person with the burn remove the chemical substance if he or she is able.

There is no longer any doubt as to the problem posed by chemical substances.

The job of glands within a body is to make chemical substances, and put them out into the body's system.

All chemical substances used in the battery can be recycled.

There are restrictions on marketing some chemical substances and how you use them.

You must use a chemical substance within its safe exposure limits.

However, most of the chemical substances mentioned in the report will not be eliminated from the environment.

These were the first research findings to show that a pure chemical substance can cause cancer.

Generally speaking, if chemical substances enter water, they destroy life.

It is difficult to imagine life without chemical substances.

Chemotherapy is the use of chemical substances to treat diseases.

There are also other chemical substances exhaled by people when breathing.

I do not think a natural substance is really a chemical substance.

The problems and hazards involved in working with new chemical substances are self-evident.

What information must be submitted about new chemical substances?

Chemical substances, traveling through air, water, or soil, often affect the environment in more than one state.

Some chemical substances have the potential to crystallize in two alternative ways.

How could I put chemicals into the air and ground, maybe the water table?

They would probably know what chemicals to use to make everything look right again.

Part of its chemicals business has been already brought public.

When these chemicals came along, of course we took them.

"I will make no decision based on some chemical in my blood!"

But I need a different lot of chemicals, and they cost money.

The second night he would not let me use chemicals.

He was working in a room where we keep chemicals.

The man said he did not like working with strong chemicals and had been having health problems.

There are some 70,000 chemicals on the market, almost half in common use.

Chemicals are a big part of the physical world around us.

"You are not going to put white chemicals in your body?"

This is the study of the chemicals in living things.

But the chemical is not expected to be available for several years.

But in other cases, they may have to use less of the chemicals.

He did not know exactly what chemicals they might be.

"Are you saying this chemical is already in the wrong hands?"

Because the house has its own well and there are chemicals in the water.

And he knew how to get the most of his workers when they used those chemicals.

Certain chemicals had to go against the back wall of the car, and others right up at the front.

So they cover some chemicals in food but not others.

It is said that 100 000 different chemicals are on the market.

Where can I get information about the health effects of chemicals?

"There are some questions of using chemicals in the air."

"But without chemicals, people could not live the way they do."