2Nd Semester Notes

2 nd Semester Notes Chemistry and Astronomy Chapters 2, 3, 4, 5 and 6

States of matter The three states of matter are ______.

• A solid has a definite shape and volume. • A liquid has no definite shape but has a definite volume. • A gas has no definite shape and no definite volume.

Elements • Can’t be ______into another substance.

Compound • ______of elements. Examples are: H20àwater CO2àCarbon Dioxide C12O22H11à Sugar C6H12O6à Glucose

Atom • The ______of an element.

Chemical Bond • The ______that holds the atoms together.

Formula • Ratio of atoms of each element in a compound. Example: Theobromine, C7H8O4N2 or Chocolate Characteristic Properties Regardless of ______, a substance has a unique characteristic property.

Type of characteristic properties 1. ______: The temperature at which a liquid boils. Water's boiling point is 100 °C. 2. Melting/Freezing Points: Temperature at which a solid turns into a ______.

Intermolecular forces (IMF’s): These are forces that hold particles ______together.

Temperature affects state. Substances with ______IMF’s become liquids and gasses at low temperatures. In contrast, substances with ______IMF’s can stay in a solid state even at extreme. Substances with strong IMF’s become liquids and gasses at low temperatures.

Changes in Matter 1. Physical Change: When the state of matter changes. Some examples are: ______(sugar molecules are dispersed within the water, but the individual sugar molecules are unchanged.) 2. Chemical Change: When a substance(s) combine or decompose into a new substance. Examples are iron rusting (iron oxide forms), ______(water vapor and carbon dioxide form) and eggs cooking.

Mixture • When two or more substances are mixed together but have ______. EX: Salt Water.

Solution • As well mixed as possible or when a substance has ______.

Pure Substance • One kind of matter with no ______in. • EX. ______.

Law of Conservation of Matter • Matter is neither ______during a chemical change. • It recombines to make a ______.

Changes in Matter Chapter 3

Solid • Definite Shape and ______.

Particles in a solid • ______and/or molecules are packed closely together and slightly vibrate.

Types of solids • ______: Arranged in a crystal-like repeating patter. • All have a distinct melting point.

• Amorphic Solid: Particles are arranged in an irregular or random patter. • Don’t have a distinct ______. • Example: ______. • Takes the shape of the container that it’s in. Polymers • Very large molecules made of a chain of smaller molecules • Polymers form when chemical bonds link large numbers of monomers in a repeating pattern.

Particles in a Liquid • Atoms and/or ______are loosely packed together.

Liquid Suspension • A mixture where particles can be______. • Examples: ______.

Viscosity of a Liquid • The ______of a liquid to flow. • The higher the viscosity, the ______it will flow. • Usually ______solids.

Gases • Have no ______and no definite volume. • Very compressible.

Particles in a gas • Particles are not touching, therefore the ______are broken. • Movement is random and independent of each other. Boyle’s Law At a ______, if the pressure of a gas decreases its volume decreases.

Pressure and Temperature of gases • When the temperature of a gas increases its ______and when temperature decreases pressure decreases.

______Law • When temperature of a gas increases its volume increases.

Energy and State Change • When a substance changes state:

• Solidà liquidà gas = ______

• Gasà liquidà solid = ______

Measuring Gases Temperature: the measure of the energy motion ______of the particles of a substance.

Measuring Gases Cont… • Pressure of a gas: The measure of the outward ______of the container.

Periodic Table of Elements

Dmitri Mendeleev • He recognized ______in the element’s approximate ______and their ability to bond with other elements.

Periodic Table • Based on atomic masses and their ______with other elements, Mendeleev constructed the first ______.

The Atom

• ______: The core of the atom that contains two different subatomic particles. • ______: Have a positive charge. The number of protons equals the number of electrons. • ______: Have no Charge • ______: Negative charge. Equals the number of protons.

Atomic Numbers, Symbols and Mass • Atomic number is the ______and the number of protons in the nucleus.

• ______

• Element Name

• Atomic mass is the all the ______and ______added together.

How to Calculate Number of Electrons • The number of ______equal the number of ______.

How to calculate # of neutrons • Atomic numbers – atomic # = # of neutrons. Groups –Families  elements in a group have very ______i.e. bonding, reactivity, valence electrons. Periods-  elements in a period are not alike, but ______as you move from left to right.

METALS  ______are classified as metals

Properties of Metals • Conductors : Metals______. • Malleable: Ability to ______. • Ductile: Ability to ______. • Many are shiny, hard and magnetic. • Reactivity: Ability to react and combine with other elements. Some are ______. Sodium (Na) and potassium (K) are some of the most reactive metals.

Alloys • Metals can easily combine into different ______. Examples of alloys • Steel: ______• Bronze: ______• Brass: ______• White Gold: ______• Yellow gold: ______

ALKALI METALS • So reactive that they are ______, only combined with other elements. Characteristics Properties: • Soft • Shiny • One valance electron ______.

Alkaline Earth Metals • Group ______metals. • Very reactive, not as reactive as ______due to having one more valence electron. • Ca: important for bones.

TRANSITION METALS • All are ______. • Fairly stable. • Fe : Iron is important for ______in your blood.

Lanthinides and Actinides • AKA Rare ______. • Placed at the bottom of the table for convenience. • They are in ______. • Uranium is used for nuclear power.

Metalloids  Non metals lack ______.  They are on the right side of the periodic table.  Physical Properties: • Many are ______. • Dull (not shiny) • ______• Low density  Chemical properties: Readily ______. Non-metals • Non metals ______. • They are on the ______. • Non metals ______to make compounds and they are ______. • In general, metals give up electrons to non-metals.

Predicting Reactions • Elements become ______as they gain more valence electrons. • As a result, atoms will ______electrons to form compounds so that they have 8 valence electrons or a full shell. • This is called the ______. However there are many exceptions, but this is an easy way to predict common reactions.

Families of Non-metals • Carbon Family is ______and is the only metal in that group and is found in all living things. Example of compound______. • Nitrogen Family is ______and Nitrogen makes up 78% of the ______. Example of compound______. • Oxygen family is ______and oxygen makes up ______of the earth’s atmosphere. Example of compound______. • Halogen family is ______Each element has 7 electrons, therefore it commonly takes one electron away from group one metals to make compounds. Example of compound______. • Noble Gases are ______They have 8 valence electrons, therefore they are ______.

Hydrogen • Not a part of ______. • Generally found as ______.

Chemical Reactions

Valence Electrons Only electrons involved in ______. The number of ______affects whether atoms bond or not.

Electron Dot Diagram or Lewis Dot Structures

Bonding • ______when a chemical reaction occurs. The bonds form when either valence electrons are transferred, taken away or shared between atoms.

Reactivity • When bonds form the atoms ______.

Ionic Bonds Electron Transfer: Atoms with ______will transfer them to an atom with four or more, causing the atoms to become stable

Ions • If an atom loses an electron it becomes a ______. • If it gains an electron it becomes ______. • Ionic bonds form as a result of the attraction between positive and ______. Covalent Bonds • When compounds are held together by ______. • The force that holds atoms together in a covalent bond is the ______for the shared pair of electrons. • Common covalent compounds are Fat, proteins, carbs, cotton and wool. • They have ______. • Poor conductors of ______. • Elements from ______bonded together. Nonpolar Bonds • Bonds cancel each other out à Typically ______.

Polar Compounds • When ______, it causes one atom to be slightly positive and the other will be slightly negative. • Electrons are pulled closer to Oxygen giving it a slight ______. • Hydrogen gets a ______because the electrons are pulled further away from hydrogen.

Water • Because water is a polar compound, it has many unique properties. • ______: Water molecules stick together. • ______: Water tends to stick to objects. • ______: Molecules on the surface are only affected by those below the surface, thus causing water drops to be spheres.

Chemical Reactions  Production of new materials that are ______from the beginning materials.  Matter can undergo both physical change and ______.

Evidence for Chemical Reactions • ______• ______• ______• ______• ______

Chemical Equations • A shorter, easier way of showing chemical reactions using symbols instead of words. • Chemical Formula – shows the ratio of elements in a compound • H2O • NaCl • CO2

Structure of an Equation • Reactants – ______• Products – ______Reactant + Reactant à Product H2 + O2 à H2O2

Conservation of Mass • The ______in a chemical reaction does not change, so the total mass of the reactants ______the total mass of the products.

Classifying Chemical Reactions  ______ ______ ______ ______

Synthesis • Two or more elements combine to form a more complex compound. • ______• Hand + kerchief à handkerchief • Example: ______

Decomposition • ______into simpler substances. • AB à A + B • Schoolbook à school + book • Example: ______

Replacement • A reaction in which one element replaces another in a compound, or two elements in different compounds trade places • AB + C à AC + B (Single) • AB + CD à AC + BD (Double) • T.V. screen + door knob à T.V. knob + screen door • ______

Writing Chemical Equations To describe a reaction accurately, a chemical equation must show the same number of each type of atom on both sides of the equation.

CO2 Subscript= ______

Mg + O2 à MgO

Coefficient is the number in ______that represents the # of molecules.

Controlling Chemical Reactions • Every chemical reaction involves energy in one of two ways: • Exothermic: ______. • Endothermic: ______.

Activation Energy • The______needed to get a reaction started.

Rates of Reaction • ______: the more particles to react the faster the reaction.

Rates of Reaction • Surface area: the more particles that are exposed in a reaction, the faster it is.

• ______: If temperature is increased, then the rate of reaction increases. • ______: Helps reaction happen by lowering activation energy. • ______: Decreases rate of reaction. • ______: Biological catalyst in our bodies that allow important bodily functions to occur.

Acids and Bases • Acid: Tastes sour, react with metals and ______. • Base: Bitter, feels slippery and ______. pH • A scale that measures whether a chemical solution is ______.

Notes: The Earth, Moon, and Sun  Astronomy – the study of the ______in space  Earth’s axis – the ______that passes through the Earth’s center and the North and South poles  Earth spinning on its axis is called its. ______ ______on its axis causes day and night.  It takes Earth about ______à a day  Revolution – the movement of one object around another object.  The ______à one revolution = one year  Orbit – Earth’s path as it revolves around the sun (oval shape).

Seasons on Earth o Four seasons: ______o Sunlight directly hits the Earth at the ______, causing these areas to be the warmest. o The sunlight that hits the poles is spread out, resulting in cooler weather. o Summer Solstice: For the Northern Hemisphere, ______day of the year on June 21st. o Winter Solstice is the ______on December 21st. o ______: Two days of the year half way between the solstice, the earth’s axis is neither pointed away or toward the sun. The daylight hours are equal to the nighttime hours. o Vernal Equinox: or ______o Autumnal Equinox: is September 23rd.

The Moon Phases of the Moon  The ______in the same amount of time it takes to rotate on its axis  Result à The near side of the moon ______.  The different shapes of the moon you see from ______.  Phases are caused by ______of the moon, Earth, and the sun.  The phases of the ______how much of the sunlit side of the moon faces Earth  When the moon’s ______or the Earth’s shadow hits the moon, an eclipse occurs  ______– when the moon passes between the Earth and the sun  ______– when the Earth is directly between moon and sun during a full moon

Tides  The ______of the sea surface due to the moon’s gravitational pull.  Every ______ 6= hours ______ 6= hours ______ ______the moon and the earth toward each other.  The closer 2 objects in space, the greater the gravitational pull.  The moon’s gravity pulls on the earth at different times and different parts of the earth  Spring Tides: Cause extra high tides because both the ______ Neap tides: ______

Structure of the Moon  The moon is ______.  It has no atmosphere because it has very little gravity.  The moon’s surface has ______.  The moon has a partially molten-iron core, that is almost completely cooled.  The moon has ______which are similar to earth quakes, but they’re on the moon.

The Sun  It makes up ______.  It holds all the planets in orbit due to its ______

The Sun’s Interior  The sun’s core produces it’s ______.

The Core of the Sun  Photosphere-The inner layer of ______.  Chromosphere- Middle layer that produces color  Corona- ______ Light and heat leaves the Sun’s surface and escapes into space, which provides the Earth’s energy.

Solar Wind  Electrically charged or magnetic particles ______.  It takes 5 days for the solar wind to reach the earth

Sun Spots and Prominences  ______, red loops of gas produced by magnetic fields.

Solar flares  Violent discharges of ______.  This can knock out ______.

Stars Galaxies and the Universe  Electromagnetic Radiation: Energy that travels ______ Visible Light: Light that you can see with your own eyes.  Wavelength: The distance from ______.  Frequency: The ______.

TOOLS OF ASTRONOMY  ______: A tool that is used to obtain information from stars by breaking up the colors they emit.  ______: Each element absorbs different wavelengths of light and shows up as lines on a spectrum.

 ______: Stars at different temperature produce different line spectra.

Characteristics of stars • Galaxy: A huge mass of ______. We live in the Milky Way Galaxy.

Distances to stars  Light Speed: Light ______. • Light Year: The distance ______.

Electromagnetic Radiation  The ______includes the entire range of radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

Wavelength: The distance from one ______to another.

Frequency: The number of ______in an interval.

Chemical compositions: Each element absorbs different wavelengths of light and shows up as lines on a spectrum.

Types of Telescopes  A ______uses convex lenses to focus light. A reflecting telescope has a curved mirror in place of an objective lens.

Four Views of the Crab Nebula  Different type of telescopes collect ______at different wavelengths. Astronomers are able to learn a great deal about the Crab Nebula by examining these different images. The images are shown at different scales.

Characteristics of Stars Star Size  Stars vary greatly in size. Giant stars are typically ______times larger than the sun and more than 1,000 times the size of a white dwarf.

Star Spectrums  Astronomers can use______to identify the chemical elements in a star. Each element produces a characteristic pattern of spectral lines.

Parallax  Parallax is the apparent change in position of an object when you look at it from different places.

Measuring Distances to Stars  Astronomers often use ______to measure distances to nearby stars.

Light Speed: Light travels at ______. Light Year: The distance light travels in a______.

The Hertzsprung-Russell Diagram  Astronomers use______to classify stars and to understand how stars change over time.

Lives of Stars  A star’s life history depends on its______. After a star runs out of fuel, it becomes a white dwarf, a neutron star, or a black hole.

Pulsar  Pulsars are spinning ______that emit steady beams of radiation.

Black Holes  The remains of the most ______collapse into black holes.

Star Systems and Galaxies

Types of Galaxies  Astronomers classify most galaxies into three main categories: 1. ______2. ______3. ______

Structure of the Milky Way  Our solar system is located in a ______called the Milky Way. From the side, the Milky Way appears to be a narrow disk with a bulge in the middle. The galaxy’s spiral structure is visible only from above or below.

The Expanding Universe Retreating Galaxies  All of the distant galaxies astronomers have observed are moving ______from our galaxy and from each other.

Moving Galaxies  The galaxies in the universe are like the raisins in rising bread dough.

Formation of the Solar System  The solar system formed from a collapsing cloud of gas and dust.