Most people like to smell food baking in the oven, but most people do not like the ____________ from their garbage.

The emphasis in this reading is that all odors travel the same way— whether they smell good or bad and whether a person is familiar with the odor or not.

In class, you smelled materials that were in _________________ containers. As your teacher opened each jar,you probably did not smell anything right away.

Each odor had to move to reach each person’s ___________________.

All odors move in the same way whether they are in a classroom, a house, or outdoors. All _________________ move away from a material and become part of the air.

Once the odor of spoiled food reaches your nose, you probably will not eat the food. Spoiled food can make you sick, so the bad ___________ warns you not to eat it.

What is all matter made up of?

Which of the following is a detector?

Scientists use the word _____________ to describe materials that people cannot smell.

Human noses can smell a material called mercaptan. ______________________ has a rotten egg odor.

When scientists add mercaptan to natural gas, the odor moves with the other gases that make up air.

You might have smelled mercaptan if your house uses natural gas for heating or cooking. If you have ever turned on the stove, but the burner does not light quickly, then you may have smelled the rotten ____________ odor.

Natural gas is safe most of the time, but if something goes wrong, the gas could be dangerous. A leak of natural gas into the air, for example, can be __________________.

Scientists used their understanding of odors and how they move to make it safe for people to heat their ____________

with natural gas.

All people notice things about the world by making observations. People use their senses to see, _________________, smell, touch, and hear what is around them.

When people notice something, they are making observations. Sometimes people think about what they see, and they wonder about why or how something happens.

Generating questions based on observations is essential to inquiry- based ________________.

In science, models are helpful in many ways. In general, scientists develop models and use them to explain _______________.

REMEMBER THAT THE ______________ OF PERFUME SPREADING THROUGHOUT A ROOM IS AN EXAMPLE OF GAS DIFFUSION

In class we smelled [odor 1] and [odor 2] that were

contained in [source]. We then drew a _______________.

During class, you slowly began to smell the odor. Since I am

across the room, it ________________ awhile for the odor to reach me.

We should understand that models show

relationships between entities (in this unit, between the source, the nose, the ____________ in the air, and

how it travels between them).

When smelling substances in close proximity, instruct students to waft (wave) the aroma toward their noses rather than sniffing the material directly. Many substances can be irritants if inhaled deeply. ____________ will be important many times in this unit.

Today we developed and used models to explain their initial ideas about (a) what an odor is made up of and (b) how an odor moves from a source to their .

The unit focuses on developing an appropriate ___________ of the particle nature of matter over time.

In order to explain _____________, such as that odors are in the jar and then you can smell them, scientists try to picture in their heads what happens.

In Lesson 1 we might ask questions about how the nose works, or why dogs can smell things that

people cannot, or any one of a number of other odor- related _______________.

People who are closer to an odor...

In which location do odors move differently?

Which of the following is a way your nose senses danger?

What is the BEST way scientists have learned to use your nose to keep people safe?

Why is natural gas dangerous?