Chemistry Grade 4

EQ: What is chemistry?

Chemistry K-W-L KnowWant to KnowLearned

History of Chemistry Ancient Egyptians Made perfumes for preserving the body Ancient Greeks Aristotle and other philosophers made detailed observations about the four elements: earth, air, wind, and water Middle Ages Alchemists tried to find ways to help people live forever Interested in turning lead into gold The word "alchemy" comes from the Arabic word for "the chemistry", originally from a Greek word meaning "fluids.” Chemistry is the branch of science that studies the composition (make-up), properties, and behaviors of matter.

EQ: What are the three basic parts of an atom?

Atoms atom- the smallest unit of an element that still retains the properties of the element electron- a negatively charged particle that circle the nucleus of an atom charge- the electrical energy contained in a particle nucleus- the center of an atom neutron- an uncharged or neutral particle in the nucleus of an atom proton- a positively charged particle in the nucleus of an atom (+)

Atom Parts of an atom – proton – neutron – electron Neutron

Bill Nye “Science Guy” Atoms 23 min

EQ: What are the three states of mattter?

States of Matter gas- a state of matter that both volume and shape change with container. liquid-a state of matter that retains its volume, but shape changes with container molecule- two or more atoms that are chemically combined physical property- a characteristic that can be observed; color, temperature, mass, volume are examples solid- a state of matter that retains its shape and volume regardless of the container temperature- the measure of how hot or cold something is weight- the measure of the amount of gravity that acts on an object; depends on an objects location in the universe

States of Matter 3 States Solid – Definite size – Definite shape Liquid – Definite volume – No definite shape Gas – No definite volume – No definite shape

Changing Between States of Matter Processes: Evaporation – Changes a liquid to a gas Condensation – Changes a gas to a liquid Freezing – Changes a liquid to a solid Heating – Changes a solid to a liquid

EQ: What are the properties of matter?

Properties of Matter density- the mass of a substance per unit of volume mass- the amount of matter in an object matter- anything that has mass and occupies space volume- the amount of space an object takes up or occupies

EQ: What is density?

Density Experiment

Archimedes Principle If the object is less dense than water (if it floats on water), it displaces a weight of water equal to the weight of the object. If the object sinks in water, it simply displaces a volume of water equal to the volume of the object.

EQ: What is an element?

Elements Chemical Symbol Chemical Name Atomic Number Atomic mass Atomic number equals the number of ____________ or ________________. Atomic mass equals the number of ______________ + _______________.

Assignment: Finish the rest of the worksheet and turn it in to your teacher.

EQ: What is a solution?

Solutions concentration- the amount of solute dissolved in a solvent saturation point: the point at which no more of a solute can be dissolved (cannot dissolve anymore) solute- any substance dissolved in a solvent (salt) solution- a homogeneous mixture of two or more substances that are blended completely (lemonade) solvent- a substance, often a liquid, that can dissolve another substance (water)

Making Crystals Materials: Cup Straw String Hot water – H 2 O Sugar (C 12 H 22 O 11 ) Teaspoon Thermometer Procedure: 1.Fill a cup ½ full with solvent (hot water). Measure and record the temperature of the solvent. 2.Measuring 1 teaspoon at a time, add solute (sugar) to the water. Dissolve completely by stirring before adding another teaspoon of solute. 3.When the solvent becomes saturated, record the concentration (amount of sugar). 4.Tie a string to the center of the straw. 5.Hang the string down into the solution (sugar + water) and allow the straw to rest across the cup rim. 6.Carefully put the cup of solution in a warm location for several days. 7.Observe results.

Bill Nye “Science Guy” Chemical Chemical Reactions 23 min

Gets Ready, Set, Dough