Compounds And Elements

Classification:  Everything in the world that has a mass is called “matter”  Matter can be classified as: Matter Pure Substance Mixture Element Ex. gold Compound Ex. water Hetero- geneous Mixture Homo- geneous Mixture

RECALL: Matter: anything that takes up space & has a mass Ex.a desk Ex.pizza Ex.silver necklace Ex.oxygen

 Mixture: combinations of two or more substances that are not chemically combined (mixed) Easily separated Ex.fruit salad Ex.sugar in coffee  Pure Substance: composed of a single substance with the same properties throughout Ex.water Ex.table salt

ssimplest form of matter MMade up of one type of particle ccannot be separated or broken down into simpler substance EEx.Oxygen EEx.Aluminum EEx.Gold EEx.Copper A pure substance can be further broken down into an element or a compound…… Elements:

 NOTE: With chemical reactions you can go from an element to compound & vise versa!!! ElementCompound H O Ex.oxygen & hydrogen Ex.water (H 2 O) H O HH

 substance made of two or more elements  can be separated into simpler substance  Ex.Water (H 2 O)  Ex.Carbon dioxide (CO 2 )  Ex.Sugar (C 6 H 12 O 6 )  Ex.Salt (NaCl) Recall, a pure substance can be further broken down into an element or a compound Compounds:

Recall, a mixture can be further broken down into a homogeneous mixture or a heterogeneous mixture……  Homogeneous Mixture: Mixture that looks uniform throughout or like one substance Only one visible part Ex.milk in coffee Ex.sugar dissolved in water  Heterogeneous Mixture: mixtures that are not uniform can see individual parts (2 or more) Ex. salad Ex.chocolate chip muffin

State whether the following are examples of an element or a compound. A gold ring Rust (Fe 2 O 3 ) Carbon monoxide (CO) Aluminum Foil Calcium element compound element

State whether the following are examples of an element or a compound or a mixture A blueberry muffin Chunky Soup Salt (NaCl) Helium Water (H 2 O) mixture compound element compound

Element Compound Mixture Compound State whether the following pictures represent an element or a compound or a mixture

Which statement best describes a compound. A)A pure substance that has a high melting point. B)A mixture that is formed by two or more elements. C )A pure substance that is formed by two or more elements.

RECALL: Matter Pure SubstanceMixture Element Ex. gold Compound Ex. water Hetero- geneous Mixture Homo- geneous Mixture Mechanical Mixture Suspension Mixture Collid Mixture 3 types of heterogeneous mixtures

Heterogeneous Mixtures A. Mechanical – Easily see two or more parts B. Suspension – very cloudy but solid part will settle on bottom C. Collid – very cloudy and solid part will not settle out to the bottom – STAYS CLOUDY

Reactions: Chemical Reactions can combine elements to make compounds (synthesis reaction) OR Chemical Reactions can break apart compounds into its elements (decomposition reaction)

Synthesis Reaction:  Makes a new substance  Sign of a chemical change  Increase in mass  Ex. If you see mass, the ONLY thing you know is that a compound was made!!! +  + 

Decomposition Reaction:  Two or more substances produced  Sign of a chemical change  Decrease in mass  Ex. If you see mass, the ONLY thing you know is that you started with a compound! +  + 

You a leave a 2g copper penny outside. Over time, the penny becomes green in color & its mass is now 2.5g. Which statements below are true? A) A chemical change occurred B) A physical change occurred C) A compound was made TRUE D) An element was made

You have 5g orange powder which you heat. As the powder is heated you noticed that a gas is given off & a silver liquid is produced. After heating you only have 1g of the orange powder left. Which substance was definitely a compound? Why? orange powder decrease in mass production of two substances

A grey colored solid is heated. The following observations were recorded Before HeatingAfter Heating Statesolid Colorgreyblack Texturesmoothgranular Mass1.75g2.5g What statement is DEFINITELY true? A) The solid after heating is an element B) The solid after heating is a compound C ) The solid before heating is an element TRUE

A)The white powder could be an element In a lab you heat 50g of a white powder in an open container. Over time, you obtain a yellow substance with a mass of 65g. Which statement is definitely FALSE? B)The white powder could be a compound C)The yellow substance could be an element D)The yellow substance could be a compound

 Mixture: 2 or more components brought together that can be separated physically  Pure Substance A single substance with the same properties throughout  Element Simplest form of matter that can not be broken down  Compound 2 or more elements chemically combined

 To identify elements or compounds: If mass increases, you know that you have made a compound If mass decreases, you know that you started with a compound

Activities  Physical Science Worksheet #3  Student Study Guide- Module 1.19 to 1-22  Other Activities: Science Quest Textbook – page 31 – 33

References  Student Study Guide – Physical Science 416/436 - MEQ  Science Quest – Grenier, Daigle, Rheaume – 1998, Cheneliere  ok/101Aatoms.html ok/101Aatoms.html  ok/103Acompounds.html ok/103Acompounds.html  Animation Factory  Google Images