Counting Atoms in Chemical Compounds
A worksheet for Grade 9 Science students to practice counting atoms in various chemical compounds, aligning with fundamental chemistry principles.
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Counting Atoms in Chemical Compounds
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Date:
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Read each question carefully and follow the instructions to count the atoms in the given chemical compounds. Show your work where required.
1. In the chemical formula H₂O, there are hydrogen atoms and oxygen atoms.
2. A subscript in a chemical formula indicates the number of of an element in a compound.
3. The chemical formula for carbon dioxide is CO₂. This means there is one carbon atom and oxygen atoms.
1. How many total atoms are in the compound NaCl (sodium chloride)?
1
2
3
4
2. In the formula Mg(OH)₂, how many oxygen atoms are present?
1
2
3
4
1. Count the number of each type of atom in the compound H₂SO₄ (sulfuric acid).
2. Explain the difference between a coefficient and a subscript in a chemical formula.
1. The compound 2CO₂ contains a total of 4 oxygen atoms.
True
False
2. In the formula (NH₄)₃PO₄, there are 12 hydrogen atoms.
True
False
Count all atoms in the following compound: Al₂(SO₄)₃