Elements and Compounds
Which of the following are NOT Elements? ; Hydrogen, Water, Carbon, Peanut Butter, Air
Water, Peanut Butter, Air
The formula for density is
Density = Mass divided by ________
Volume
Billy noticed his Italian salad dressing separated into water, oil and seasoning overnight. This is because Italian salad dressing is an example of this type of mixture.
Heterogenous
True or False; Making Koo-laid is an example of a physical change?
True
Name two chemical changes
Multiple answers; rusting, burning, cooking, baking, grilling, heating, combustion, exploding, rotting, spoiling etc.
NOT dissolving!
Elements can be divided into infinitely small units we call __________
atoms
Select the liquid which is the most dense:
gasoline, water, honey, dish soap, vegetable oil, rubbing alcohol
honey
Homogenous
Name at least three of the physical changes water can undergo. (Hint- phase changes )
Freezing, Melting, Evaporation (boiling), Condensation, Sublimation, Deposition
From the following, choose what are NOT chemical properties; Flammability, reacts with acid, dissolves in water, shiny, produces gas, feels fuzzy
Dissolves in water, shiny, feels fuzzy
By definition, compounds must be made up of at minimum ________ pure substances
Two or more
density can be measured in milliliters (mL) or in g/cm3, which means ______________
grams per cubic centimeters
By definition, a mixture is two or more substances that have been combined. These substances CAN BE SEPARATED using _________ methods
Physical
Name THREE physical changes
Multiple answers; Cutting, painting, coloring, bending, flattening, ALL PHASE CHANGES, dissolving, etc.
Beth missed last week. In your own words, tell Beth how you can tell if a chemical change has occurred
The initial substance has changed into a different substance. Examples- cooking, burning, a reaction takes place, gas produced, etc.
The internet is a great resource to check if a substance is an element. What other, more reliable resource could you use?
Periodic Table (Of Elements)
DAILY DOUBLE!!! Solve for density: The mass of an object is 150 grams. The object is a rectangular box that measures 5cm tall, 6cm wide, and 10cm long
D= 150/ (5cmx 6cmx 10cm) = 150/300 = 0.5g/cm3
Provide THREE examples of a heterogenous mixtures
Multiple answers possible; salad, pizza, rocks, OJ with pulp, skittles, M&M's etc.
Select the physical properties from the following; transparency, solubility (can it dissolve), changes substance when heated, color, melting point, density, reacts with oxygen
transparency, solubility, color, melting point, density,
These TWO chemical changes occur commonly when metals are exposed to humidity and air
Rusting / tarnishing/ corrosion / spotting etc
Please list three metals that are elements
Numerous answers; iron (Fe), copper (Cu), Nickel (Ni), Titanium (Ti), Gold (Au), Silver (Ag), Zinc (Zn), Aluminum (Al), Lead (Pb), Chromium (Cr)
Solve for mass ; When placed in a graduated cylinder, an object raises the water from 10mL to 22mL. The density of the object is 3 g/mL
Mass = 36 grams
Density = 3 g/mL= Mass/ (22-10mL= 12mL )
12 x 3 = 36 grams
Unlike a mixture, elements, molecules, compounds and atoms are classified as __________ ____________
Pure Substances
On a pop quiz Mr. Steube asks you to describe how you know, with 100% confidence, a physical change has occurred?
There is no change to the substance, it remains the same substance as before the change.
DAILY DOUBLE!!!! This chemical change uses strong Hydrochloric acid to break down mixtures and compounds. Typically occurring three times a day
Digestion (eating acceptable)