Elements compounds and mixtures

• What are the four key concepts in chemistry for this topic

  Element, compound, mixture, and molecule
• Why is it essential to understand elements, compounds, mixtures, and molecules?

  They are fundamental concepts in chemistry
• How many different elements are there approximately?

  Around 100 different elements
• What does each symbol in the periodic table represent?

  A different element
• What is the symbol for magnesium?

  Capital M followed by lowercase g
• What is the symbol for sulfur?

  Capital S
• What defines an element?

  All atoms in an element are the same
• What happens when magnesium and sulfur atoms are chemically combined?

  They form a compound called magnesium sulfide
• What is the definition of a compound?

  Two or more different elements chemically combined
• What does "fixed proportions" mean in a compound?

  Elements are combined in a specific ratio
• How do the properties of compounds compare to the elements they are made from?

  Compounds usually have different properties
• What is required to separate a compound back into its elements?

  A chemical reaction
• What is a mixture?

  Different elements or compounds not chemically combined
• How can mixtures be separated?

  Using physical separation techniques
• Name one physical separation technique.

  Filtration
• What is a molecule?

  Elements chemically combined, same or different
• What distinguishes a compound from a molecule?

  A compound has different elements combined
• What elements are found in methane?

  Carbon and hydrogen
• What elements are found in water?

  Hydrogen and oxygen
• What elements are found in ammonia?

  Nitrogen and hydrogen
• Are chlorine and oxygen molecules compounds?

  No, they are not compounds
• What is the difference between a molecule and a compound?

  A molecule can be the same element combined
• What are the key differences between elements, compounds, and mixtures?

  • Elements: Pure substances with identical atoms
  • Compounds: Two or more different elements chemically combined
  • Mixtures: Different elements or compounds not chemically combined
• What are the physical separation techniques mentioned?

  • Filtration
  • Distillation
  • Crystallization
  • Chromatography
• How do the properties of compounds differ from their constituent elements?

  • Compounds have distinct properties
  • Elements retain their individual properties