Chemistry: Chapter 2 Matter
Terms
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- What are physical changes
- Effect only the physical properties. You don't make something new. There are alterations in the form, but not in the matter itself. Crushing, tearing, and changes in state are examples of physical properties.
- What are examples of physical properties.
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Breaking up a piece of chalk, melting an ice cube (phase change) dissolving salt in water, magnetizing iron, boiling water.
H2O(s) - H2O(l) - What are chemical changes.
- A change that produces one or more new substances. You make something new.
- Examples of chemical changes.
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Burning toast, cooking an egg, wood burning, iron rusting, wood rotting. Chemicals getting rearranged.
Ni+2AgNO3 - Ni (NO3)2 + 2Ag - Definition of intensive
- Innate or inborn. These properties can be used to identify a substance. The amount of substance will not matter.
- Examples of intensive
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Melting point, boiling point, density, color,
The density of H2O is 1.0g/mL whether you have 10 mL or 500 mL. - Definition of extensive
- Properties that give you amounts. They cannot be used to idenify a substance.
- Examples of extensive
- Length, mass, volume.
- Who's Lavosier
- Discovered that the number and kinds of elements stay the same, they just got rearranged. He proposed the law of conservation of matter.
- Law of Conservation of matter.
- Matter is neither created nor destroyed by a chemical change. The only exception is nuclear chemicals.
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THe most common element in the earth is
The most common element in the universe -
oxygen
hydrogen - Oxygen can be in a:
- free state O2 (g), elemental state, combined state - FeO or H2O
- Matter classifications
- elements, compounds, and mixtures.
- elements
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substance that cannot be separated into simpler substances by a chemical change.
EX. Helium, oxygen, hydrogen - The periodic table
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Contains all of the known elements (over 100 different kinds)1 or 2 letter abbreviations, the first letter is always capitalized. The elements are named after people, places, planets, etc.
EX. Plutonium, Californium, Curium (scientist) - compounds
- a substance that contains 2 or more different elements combined in a fixed proportion.
- Examples of compounds
- EX. table sugar, C12H22O11, NaCl (table salt) MgO(s)
- substances
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elements and compounds
EX O2(g), Al (s)(aluminum foil), H2O. - 2 Ways to idenify properties of matter
- physical and chemical properties
- Physical properites
- characteristics that you can observe without making something new.
- Examples of Physical properties
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density, color, meliting point, boiling point, odor, taste, hardness, electrical conductivity, etc.
EX melting an ice cube - Chemical properties
- characteristics that describe how the substances interacts with or fails to interact with other substances to produce new substances.
- Examples of chemical properties
-
EX. flammability, reactivity with other substances
EX. L, Na, and K all react vigorously to water.
EX. 2Na (s) + 2 H2O(l) - 2NaOH (aq)+ H2 (g) - Matter
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anything that has mass and takes up space.
EX a ball, air in the room, a glass of water - Not Matter
- a radio wave, a beam of sunlight, an X ray bean. These are formes of energy.
- The best way to measure matter
- Mass.
- Volume
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depends on temp
EX 10 L of H2O(g) at 100 C vs 1.0L of H2O (l) at 20 C (room temp) Much more H2O at room temperature. - Weight
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depends on where you are
EX on the moon you weight 1/6 of what you weigh on Earth. At the poles you have a slightly different weight. - Solid
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Fixed volume and shape, high density
EX ice, chair - Liquid
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fixed volume, but variable shape, high density
EX liquid, water, mercury at room temperature. - Gas
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no fixed shape or volume expands to fill any container it occupies, low density.
EX air, helium - Plasma
- high energy state, interior of sun.