The goal of this activity is for students to practice reading chemical formulas, naming the elements in the formula as well as how many, and also drawing (making) a model of that molecule.
This activity can be very hands on (it helps to explain the activity the day before you do it, so that once it comes time for class they can start immediately because with the 2 pages it is a lot of formulas to work through)
Students will first: read the formula, then count the number of elements, then name the elements, then count the total number of atoms (all this information is recorded in the table) The last column labeled "key" is a place for student to pick a color for each element (ex: red is Hydrogen and Blue is Oxygen) or if you are doing foods (ex: H = marshmallows, and O = gum drop)
**its a lot more fun to do it with food and have the students build the model:
Supplies: toothpicks, and various types of food that can be stuck by the tooth pick (ex: marshmallows, gum drops, gummy bears, Carmel, etc) **you would only need 4 different types because no molecule exceeds 4 different elements.
**If you choose not to do models you can just have students draw a diagram in the "key" column and use different colors for the elements **
After the students completes the table for that molecule then they can build it with the toothpicks and candies. (unless you buy a lot of supplies the students will have to break their models as they go) After it is built they can move onto the next molecule and start the whole process again.
To add and element of difficulty you could have students researching the exact shape of the molecule (is it in a line, a circle, more spread out like a tree branch) **this option might work well in partners) **
The activity CAN be used as a homework assignment: they will count how many elements are in the given molecule, name the elements, count how many atoms it contains, and then the column for "key" can be a place where they can sketch a diagram of the molecule (with different colors to represent the different elements)