IS 352 Test 1

• 1. Observing
• 2. Measuring
• 3. Classifying
• 4. Inferring
• 5. Predicting
• 6. Experimenting
• 7. Hypothesizing
• 8. Explaining
• 9. Communicating

The candle was described qualitatively and quantitatively before it was lit, during burning and after burning.

Ice cubes were placed in a beaker. Observations were made and recorded. The height of the water in the beaker was measured before melting and after melting. The height did not change because the ice displaced the water and when it melted it filled the space up.

Buttons and "wild things" were classified as a binary classification system and a multi-stage classification system.

Why does moisture collect on a beaker of ice water? Because room temperature is warmer than the ice water and causes condensation. The condensation comes from the moisture in the air. We can show that the moisture does not come from inside the glass by adding food coloring to the water.

The warmer water dissolved the Alka-Seltzer tablet faster than cooler water. The manipulated variable was the water temp., the responding variable was the time it took for the tablet to dissolve, and the control variables were the size of the tablet, the brand of the tablet, the water, the plastic cups, and the amount of water.

What's in a bag of M&M's? Predict the number of M&M's in a bag, the number of each color, and the most and least common colors. Compare data with the rest of the class groups and chart the data. On average there were more orange M&M's and the least amount were the red M&M's.

Tanagrams - one group member secretly made a design and tried to guide the other group members only with words on how to create the design. Not easy.

The stuff that everything is made of, or anything that has mass and volume

The amount of matter in an object, expressed in grams

The measure of the force exerted on an object by the pull of the Earth's gravity, expressed in Newtons

the amount of space taken up by an object, defined by l x w x h, or mL

constant composition with a specific set of properties

basic building blocks of matter

2 or more elements

2 or more pure substances where each substance will keep its own identity, does not form a new substance. i.e. sweet tea

• Physical Properties - characteristics of an object that can be observed or measured, can be changed without changing the object itself
• Chemical Properties - chemical changes the ability of matter to change into a new substance that has different properties. i.e. sterling silver -> (oxidation) -> black color (petina)

• 1. gas is produced - fizzing
• 2. color change - rust
• 3. temperature change
• 4. produces light

• Homogeneous mixture - well mixed, appears to be uniform but proportions can vary. i.e. sugar in a glass of tea
• Heterogeneous mixture - not uniform, unevenly mixed

• Liquid - definite volume and indefinite shape
• Solid - definite volume and definite shape
• Gas - indefinite volume and indefinite shape

The wick and wax work together as a system. The wax is the fuel and the wick transports the fuel to the flame. Without oxygen the flame cannot burn.

Each substance (granulate sugar, table salt, baking soda & cornstarch) behave differently when mixed with the various substances (water, iodine & vinegar). The biggest reaction came from mixing iodine with cornstarch. The cornstarch hardened and turned black. the other came when mixing vinegar and baking soda, which produces a gas evident from fizzing. Both of these are chemical reactions.

Liquid or Solid? It doesn't have a definite shape, so it can't be a solid. It has a definite volume and no definite shape so it fits the definition of a liquid.

• + Heat NRG
• Solid -> Liquid = Melting
• Liquid -> Gas = Evaporation
• Solid -> Gas = Sublimation
• - Heat NRG
• Gas -> Liquid = Condensation
• Liquid -> Solid = Freezing
• Gas -> Solid = Deposition

The energy absorbed or released during a change of state.

the amount of heat it take to raise 1 gram of water 1 degree Celsius

the temperature at which the air must be cooled in order for condensation to occur

change of state from a gas to a liquid with a loss of heat energy

description of the amount of water vapor in the air

the maximum possible amount of water vapor the air can hold at a given temperature and pressure

in a graduated cylinder the meniscus is read at the bottom of the curve

Condensation is a change of state when a gas turns into a liquid with a loss of heat energy. The ice cools the sides of the cup which cools the warmer air that contains the water vapor very close to the outside of the cup. Water vapor gathers on the outside of the cup as condensation.

Condensation first started showing on the cup at 5 degrees Celsius, when the temperature had dropped 19 degrees.

• Proton - inside nucleus, + charge, atomic #, identification of element depends on the number of protons
• Electron - outside nucleus, - charge, # always = # protons, influence chemical reaction
• Neutron - inside nucleus, no charge

the order of an element in Mendeleyev's table of the elements; equal to the number of protons in the nucleus

Protons + Neutron = Atomic Mass

2 or more atoms are combined, smallest unit of a compound

• Rows: periods, there are 7
• Columns: family - there are 18, they react in the same way
• Group 1: Alkali Metal - very reactive, hardly find in nature
• Group 2: Alkaline Earth Metals
• Group 3 - 12: Transition Elements
• Group 13 - 16: BCNO
• Group 17: Halogens - non-metals, 5 elements, combine with alkali metals for form salts
• Group 18: Noble Gases - found in Earth's atmosphere, colorless and odorless
• Red Symbols: Gases
• Solid Black Symbols: Solids
• Blue Symbols: liquids at room temperature
• Outlined: Synthetic

• Metal (left hand side):
• Silver gray in color
• Malleable
• Shiny metallic luster
• Can be magnetic
• Good conductors of heat and electricity
• High densities
• Non-Metals (right hand side):
• Not shiny
• Transparent
• Brittle - will shatter
• Not magnetic
• Not conductors of heat or electricity
• Low density
• Some gases at room temp., some liquids & some solids
• Metalloid (semi-conductors in red outline):
• Solids
• Dull or shiny
• Malleable or brittle
• Density varies
• Conduct heat and electricity better than non-metals but not as good as metals
• Has properties of metal and non-metals

Bromine and mercury

an attractive force that holds atoms together in a compound

The sphere of water molecules around each dissolved ion.

attraction of like molecules

attraction of dissimilar molecules

a change in matter in which different chemical substances are created by breaking or forming chemical bonds

Water-loving, readily bonds with water

does not like water, i.e. oil

chemical reaction occurring or formed with absorption of heat

chemical reaction occurring or formed with the release of heat

• Covalent - formed by sharing a pair of electrons, generally, non-metallic elements
• Polar - unequal sharing
• Non-polar - atoms share electrons equally
• Ionic - atoms transfer electrons, in general a metal reacts with 1 or more nonmetals
• Metallic - formed between 2 or more metals, give electrical conductivity
• Hydrogen - atoms share electrons in a water molecule

• 1. The only substance found naturally on Earth in all 3 states
• 2. Temperature scales all based on water
• 3. Universal solvent
• 4. Density
• 5. Cohesion
• 6. Polarity of water - water attracts other polar molecules like sugar which is hydrophilic

Practice

Matter is neither created nor destroyed during a chemical reaction

An oxidizing chemical change where an element's electron loss is accompanied by a simultaneous electron gain.

• 1. Combination reaction: x + y -> xy
• 2. Decomposition reaction: xy -> x + y
• 3. Replacement reaction: xy + z -> xz + y

The vinegar reacted with the steel wool and produced heat energy. Evidence of a chemical reaction: produced rust, heat, and moisture

• Change hydrogen peroxide into water and oxygen with the aid of a potato
• Tiny bubbles form and rise to the top
• The potato releases oxygen to form bubbles
• Decomposition Reaction: H₂O₂ >> 2H₂O_(l) + O_{2 (g)}
• The potato contains enzymes catalase that speeds up the reaction.

Mix yeast with hydrogen peroxide. The yeast reacted to the hydrogen peroxide and heat energy was released raising the temperature of the mixture. Evidence of a chemical reaction: heat is produced, bubbles produced

• The Epsom salt absorbed the water's natural heat energy to split apart the magnesium and sulphate therefore making the water cooler.
• MgSO₄ + H₂O

• Everything is mad of chemicals
• Chemicals react to make new chemicals
• Electrons hook together
• Chemicals react with chemicals in the air and give off heat
• Water is the most important chemical
• 92 pure elements
• Alfred Nobel - Swedish chemist who invented dynamite