🔬 Part 1: Atomic Structure and Definitions

1. Label the parts of an atom. Fill in the blanks:

The center of an atom is called the _____________ and contains positively charged _____________ and neutral _____________. The negatively charged _____________ orbit around the outside.

2. Which of the following best describes an atom?

The smallest unit of matter that retains properties of an element

Two or more elements bonded together

A mixture of different substances

A building block of proteins

3. What is the difference between a molecule and a compound?

There is no difference - they are the same thing

Molecules contain only one type of element; compounds contain different elements

Compounds contain only one type of element; molecules contain different elements

Molecules are smaller than compounds

4. Check all examples that are compounds:

H₂O (water)

O₂ (oxygen gas)

CO₂ (carbon dioxide)

N₂ (nitrogen gas)

NaCl (salt)

🧬 Part 2: Sorting and Classification

5. Sort the following into the correct categories. Write each letter in the appropriate box below:

Items to sort:

A) Single carbon atom (C) B) Water molecule (H₂O) C) Oxygen gas (O₂) D) Glycine amino acid E) Single hydrogen atom (H) F) Carbon dioxide (CO₂)

ATOMS:

MOLECULES (same elements):

COMPOUNDS (different elements):

AMINO ACIDS:

6. Why are amino acids important in living organisms?

They help atoms bond together

They are the building blocks of proteins

They make up the periodic table

They are the smallest particles of matter

✏️ Part 3: Apply Your Knowledge

7. Explain in 1-2 sentences how atoms combine to form molecules:

8. Give one example each:

An atom: _______________

A molecule: _______________

A compound: _______________

9. True or False: All compounds are molecules, but not all molecules are compounds.

True

False

Explain your answer: ________________________________

Atoms to Molecules Sorting

Atoms to Molecules Sorting

🔬 Part 1: Atomic Structure and Definitions

🧬 Part 2: Sorting and Classification

✏️ Part 3: Apply Your Knowledge

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