Elements, compounds, and mixtures
Pure Substances and Mixtures · Chemistry
Study notes
Classify: (a) iron nail, (b) sugar dissolved in water, (c) carbon dioxide, (d) brass. Step 1: Iron nail — one kind of atom (Fe) → element. Step 2: Sugar + water — sugar molecules mixed in water, no new substance → mixture (compound dissolved, but the mix is a mixture). Step 3: Carbon dioxide (CO₂) — carbon and oxygen chemically bonded in fixed ratio → compound. Step 4: Brass — copper and zinc metals mixed, variable ratio → mixture (an alloy).