STUDENT NAMES IN GROUP___________________________________________________________________________ Period_________GUIDED INQUIRY

1. Examine the four models below. What substances are represented? (1)_________________________________(2)____________________________ (3)_______________________________ (4) ________________________________

(2) Oxygen = O2

(4) Carbon dioxide = CO2

(1) Water = H2O (3) Nitrogen = N2

2. What are the chemical symbols for the four substances? (1)_____________ (2)____________ (3)_____________ (4)_____________

3. Do you think the colors might have a meaning? If so, complete the sentence below about the color red. In these models, the color red means _____________________________________________________________________ .

4. In the models, each sphere represents an atom. Complete the chart below by looking at the models.

5. Study the chart you just made above. How are substances #2 and #3 different from #1 and #4? ______________________________________________________________________________________________________

______________________________________________________________________________________________________ .

Name of Substance Number of Atoms Number of Different Colors1. _____________________________ ___________ ___________2. _____________________________ ___________ ___________3. _____________________________ ___________ ___________4. _____________________________ ___________ ___________

6. ELEMENTS are made of only one type of atom, the smallest part into which a substance may be divided. Based on the models, which substances do you think are ELEMENTS?

_______________________________________________________________________________________________

7. COMPOUNDS are made of two or more different elements. Based on the models, which substances do you think are COMPOUNDS? ___________________________________________________________________________________________________________

8. What do you think the numbers mean on the models? ______________________________________________________________ __________________________________________________________________________________________________________

9. The EASY way to know if a substance is an ELEMENT or COMPOUND has to do with capitalized letters in the chemical symbol. Study the chemical symbols of the substances, then WRITE A RULE explaining how to know the difference between an element and a

compound. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________

10. Look at the model below. Based on its color and number of spheres, what do you think it is? The model represents an ___________________ of ___________________ .

BONUS: List which ELEMENT each color represents in the models. RED = _______________________ BLACK = _______________________ BLUE = _______________________ GREEN = _______________________

Using the RULE you wrote for identifying elements and compounds, label the followingas either element (E) or compound (C):

NaHCO3 ________ F ______ C12H22O11 ______Al ______ SiO2 ______ SiO2 ______Fe ______ Sn ______ NaCl ______CaCo3 ______ He ______ B ______C ______ Cu ______ Ag ______MgSO4 ______ S ______

NOW, rewrite your RULE (if needed): ____________________________________________________ ______________________________________________________________________________

Chemical Name of SubstanceFormula

Element or Compound?

Elements found in the common substance

NaHCO3

Al

Fe

C

MgSO4

S

NaCl

SiO2

Sn

He

Cu

Ag

CaCo3

EXTENSION: Go to stations to identify these common substances by their chemical formulas. Determine if they are elements or compounds. Identify which elements make up each substance. (Hint: Ignore the numbers.)