7.6B STAAR Review

Fill in the Blank

How many Elements are in the compound C₂H₈O ?

Multiple Choice

How many nitrogen atoms are there?

• 4

• 8

• 10

• 20

Multiple Choice

The blue numbers in the image below represent ________

• I don't know, and don't want to try
• coefficients
• subscripts
• none of the answers are correct

Fill in the Blank

How many total atoms are present in FOUR molecules of sulfur dioxide?

SO₂

Multiple Choice

What is the total number of atoms in the chemical formula 3Ba(OH)₂?

• 12

• 15

• 18

• 9

Fill in the Blank

A student is using colored blocks to build a model of calcium phosphate, Ca3(PO4)2. Calcium is represented by blue blocks, phosphorus by orange blocks, and oxygen by red blocks. 

To build the model, how many orange blocks should the student use?

Fill in the Blank

How many more atoms of Oxygen are represented in the formula BaSO_⁴ than in the formula Ba(OH)₂ ?

Hotspot

The names and chemical formulas of four substances are shown in the chart. Which substance listed in the chart is made up of the most atoms? Click on the name of the substance.

Multiple Select

The table shows the chemical formulas for four substances. Which substances have the same number of carbon atoms? 

• Substance 1

• Substance 2

• Substance 3

• Substance 4