Molecules and Compounds
Grade 7 · Science · Chemistry of Life · Maryland, USA
Lesson Summary
Understand how atoms bond together to form molecules and compounds.
Explanation
When two or more atoms bond together, they form a molecule. If the atoms are of different elements, the molecule is also called a compound. For example, H₂O (water) is a compound made of two hydrogen atoms and one oxygen atom. Atoms bond because they seek a stable arrangement of electrons. Ionic bonds form when atoms transfer electrons, while covalent bonds form when atoms share electrons. The chemical formula tells you exactly which atoms and how many are in each molecule.
Practice Questions
Q1: What is the difference between a molecule and a compound?
Answer: A molecule is any group of bonded atoms. A compound is a molecule made of atoms from two or more different elements. All compounds are molecules, but not all molecules are compounds (like O₂).
Q2: What does the chemical formula CO₂ tell you?
Answer: It tells you that one molecule of carbon dioxide contains one carbon atom and two oxygen atoms.
Q3: What is the difference between an ionic bond and a covalent bond?
Answer: In an ionic bond, one atom transfers electrons to another. In a covalent bond, atoms share electrons.
People Also Ask
What is Molecules and Compounds in Grade 7 Science?+
Molecules and Compounds is a lesson in the Chemistry of Life chapter of Grade 7 Science. It is part of the Maryland, USA school curriculum and covers key concepts that students need to understand at this level.
What grade level covers Molecules and Compounds?+
Molecules and Compounds is taught in Grade 7 as part of the Science curriculum in Maryland, USA.
How can I help my child with Chemistry of Life in Science?+
Start with the lesson summary and explanation on this page. Practice the questions provided, then use TutorTom for personalized, step-by-step help with Chemistry of Life topics.