Chem 1 Lesson 1 Elements are pure substances

Chem 1 Lesson

1. Elements are pure substances that cannot be broken down into any simpler substances. They are all listed in the periodic table of the elements. 2. Examples include IRON, COPPER, HELIUM, OXYGEN, LEAD, and GOLD. There are 118 known elements. 3. The smallest part of an element is an ATOM. 4. When 2 or more atoms bond together, that forms a new pure substance, called a COMPOUND. Examples include WATER (H 2 O), GASOLINE (C 8 H 18), TABLE SALT (Na. Cl), and SULFURIC ACID (H 2 SO 4).

5. If you just PUT 2 or more substances together, but they DO NOT REACT, you have just MIXED THEM TOGETHER. (these can be 2 or more elements, 2 or more compounds, or a compound an element). We call this a MIXTURE. 6. Elements are pure and have unique properties. Compounds are pure and have unique properties. Mixtures are not pure substances; they keep the properties of the substances they are made from.

Substance Formula Pentose (a kind of sugar) C 5 H 10 O 5 8 Salty Water Na. Cl + H 2 O 9 Vinegar HC 2 H 3 O 2 10 Helium 7 11 (acetic acid) (for balloons that float) Ethanol (alcohol in wine & beer) He C 2 H 5 OH Is it an element, compound, or mixture? (First) Is it pure or mixed? (Second) How many total atoms does it contain? (last)

Substance Formula Is it an element, compound, or mixture? (First) Pentose (a kind of sugar) C 5 H 10 O 5 Compound 8 Salty Water Na. Cl + H 2 O Mixture 9 Vinegar HC 2 H 3 O 2 Compound 10 Helium He Element C 2 H 5 OH Compound 7 11 (acetic acid) (for balloons that float) Ethanol (alcohol in wine & beer) Is it pure or mixed? (Second) How many total atoms does it contain? (last)

Substance Formula Is it an element, compound, or mixture? (First) Pentose (a kind of sugar) C 5 H 10 O 5 Compound Pure 8 Salty Water Na. Cl + H 2 O Mixture Mixed 9 Vinegar HC 2 H 3 O 2 Compound Pure 10 Helium He Element Pure C 2 H 5 OH Compound Pure 7 11 (acetic acid) (for balloons that float) Ethanol (alcohol in wine & beer) Is it pure or mixed? (Second) How many total atoms does it contain? (last)

Substance Formula Is it an element, compound, or mixture? (First) Pentose (a kind of sugar) C 5 H 10 O 5 Compound Pure 20 8 Salty Water Na. Cl + H 2 O Mixture Mixed 2+3=5 9 Vinegar HC 2 H 3 O 2 Compound Pure 8 10 Helium He Element Pure 1 C 2 H 5 OH Compound Pure 9 7 11 (acetic acid) (for balloons that float) Ethanol (alcohol in wine & beer) Is it pure or mixed? (Second) How many total atoms does it contain? (last)

One Element from the Periodic Table – Md (for Mendeleev, the “Father of the Periodic Table) 12. 13. 14. 15. 16. 17. 18. 19. What is the Atomic Number of this element? Skip this one! What is the NAME of this element? What is the ATOMIC MASS of this element? What is the number of electrons of this element? What is the number of protons of this element? What is the number of neutrons in this element? What parts are in the nucleus and what flies around the nucleus? 101 Md (258)

One Element from the Periodic Table – Md (for Mendeleev, the “Father of the Periodic Table) 12. What is the Atomic Number of this element? 101 13. Skip this one, okay? 14. What is the NAME of this element? Mendelevium 15. What is the ATOMIC MASS of this element? 258 AMU 16. What is the number of electrons of this element? 101 electrons 17. What is the number of protons of this element? 101 protons 18. What is the number of neutrons in this element? 258 – 101 = 157 neutrons 19. What parts are in the nucleus and what flies around the nucleus? The nucleus has the protons and the neutrons. Electrons fly around the outside of the nucleus. 101 Md (258)