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Topics

Common Mistakes

What is Chemistry?

  • Chemistry is the study of matter.

  • Matter makes up everything around us, including us.

  • Matter is made up of small subunits called atoms.

  • The behavior of matter depends on what its atoms are doing.

Matter

  • The phrase "state of matter" means the same thing as "phase of matter." There are 3 phases: solid, liquid, and gas.

  • When matter changes its state (or phase), it is transforming from solid to liquid, liquid to solid, solid to gas, gas to solid, liquid to gas, or gas to liquid. Yes, all these transformations are possible—given the right conditions.

  • A state (or phase) change is an example of a physical change. A chemical change has not occurred because the substance, or chemical in question, is still the same. It is just in a different form.

Elements

  • An element is the building block of chemistry. It is a pure substance that may be combined with other elements to build a chemical compound such as water, or H2O.

  • An atom is a subunit of a specific element.

  • Chemical compounds consist of multiple atoms attracted to one another. The atoms must be from at least two different elements.

  • There are currently 118 known elements. Unknown elements also exist. There are spaces reserved for them on the periodic table.

Atoms

  • An atom is a small subunit of matter. It was once thought to be the smallest subunit of matter, but this is no longer the case.

  • Atoms consist of a nucleus, the core, and electrons, which surround the nucleus.

  • The nucleus contains both protons and neutrons.

  • Electrons are negatively charged.

  • Protons are positively charged.

  • Neutrons are, well, just neutral little guys.

The Periodic Table

  • The periodic table is organized such that atomic numbers increase as you go from left to right.

  • The atomic number is the number of protons found in atoms of any particular element.

  • Chemical families generally correspond to vertical columns on the periodic table and represent elements that share chemical characteristics.

Bonding & Chemical Reactions


  • Atoms are joined together by a chemical glue called "bonds."

  • Electrons are important for many different types of bonds.

  • Electron transactions are at the heart of chemical reactions.

  • In a chemical reaction, atoms rearrange in novel ways, finding new bonding partners.

  • Chemical equations use symbols to represent what is occurring in a chemical reaction.

  • Reactants are always listed on the left hand side of the arrow in a chemical equation.

  • Products are always listed on the right hand side of the arrow in a chemical equation.

Lab Tips

Below are some common mistakes students make when preparing for a lab. Don't get caught making these blatant blunders. Bleh.
  • Planning on reading the directions as we go. This is a no go.
  • Wearing contact lenses. Yes, we know contact lenses may be more comfortable, but plan on wearing glasses, under your goggles, for all lab occasions. While goggles are not the most fashionable accessories, we promise that the little lines they leave on your face will fade...eventually.

  • Wearing shoes that expose too much toe. Scandalous. Please keep your toes hidden from view and protected from any falling glass or hot substances by wearing close-toed shoes.

  • Wearing hair down. Let's keep hair safe from all fire and chemicals. Always tie it back before a lab.

  • Using equipment before becoming familiar with it or not checking it to ensure it is in working order.

  • Bringing substances close to the nose...no no no. We waft. Practice the royal wave and only inhale slowly.
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