DOCSLIB.ORG

Pure Element Mixture Suspensions, Heterogeneous Mixture Solution

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

ACP and Chemistry 1 Unit 1 Review Name: ________________________________________ Equipment, Safety, Density, Sig. Fig.’s, Matter & Properties Date: _________________________________________ Classify each of the materials below. In the center column, state whether the materials is a pure substance or a mixture. If the material is a pure substance, further classify it as either an element or a compound in the column to the right. Similarly, if the material is a mixture, further classify it as homogeneous or heterogeneous in the column to the right and note if it is a solution, colloid or suspension. Element or Compound, Material Pure Substance or Mixture Homo/Heterogeneous, solution colloid or suspension 1. Iron filings (Fe) Pure Element 2. Orange Juice (with pulp) Mixture Suspensions, Heterogeneous 3. Pacific Ocean Mixture Solution, Homogeneous 4. Air inside a balloon Mixture Solution, Homogeneous 5. Brass (Cu mixed with Zn) Mixture Solution, Homogeneous 6. Muddy water Mixture Suspensions, Heterogeneous 7. Baking soda (NaHCO3) Pure Compound 8. Lucky Charms Mixture Heterogeneous 9. Milk Mixture Colloid, Homogeneous 10. Chromium (Cr) Pure Element 11. Using the equipment from your lab drawers, what item would be the best to use for each of the following: a. Measuring 120 mL of water ___________Graduated Cylinder_____________________________________________ b. Storing 300 mL of NaOH solution _______ Beaker or Erlenmeyer Flask________________________________ c. ‘Topping off’ a graduated cylinder to 10.00 mL _____ Eye Dropper_______________________________________ d. Transferring a small sample of a solid from its container to a beaker______ Spatula or Tweezers____ 12. A 5.61-gram sample is placed in 14.56 ml of water making the water rise to 17.22 ml. What is the density of the sample? 2.10902255639 g/mL 2.11 g/mL g 13. An object with a density of 2.720 /mL has a mass of 12.66 g. If the object is placed in 20.00 mL of water, to what volume will the water rise? 4.65441176471 mL 4.65 mL 14. A rectangular solid has a mass of 264.1252 g and the dimensions of 1.31 cm by 2.2 cm by 10.45 cm. Determine the density of the solid providing you answer with appropriate significant figures. 8.804173333333 g/mL 8.8 g/mL 15. Determine the number of significant figures in each of the following numbers. a. 5.9100 __4_____ c. 0.0001200 __4___ e. 203 __3_____ b. 0.00385 __3_____ d. 391000 __3___ f. 3010 _3_____ 16. Round the following value to the required number of significant figures: a. 86753090 to 3 sig. fig. __86800000 or 8.68x107_ c. 45319001 to 3 sig. fig. _45300000 or 4.53x107____ b. 0.00087642 to 2 sig. fig. __0.00088 or 8.8x10-4___ d. 0.3718912 to 4 sig. fig. _0.3719 or 3.719x10-1____ 17. Perform the following calculations providing the answer with appropriate number of significant figures. a. 5.40 + 9.811 + 6.2114 + 4.211 = 25.6334 25.63 c. 0.00212 x 0.0073 x 0.001321 = 2.0x10-8 b. 0.00212 + 0.0073 – 0.001321 = 0.008099 0.0081 d. (5.40 x 9.811 x 6.2114) / 4.211 = 78.1 18. Compare and contrast the following terms: a. mass & matter: mass is the measure of the amount of matter, matter is anything that takes up space & has mass__ b. atom & compound _an atom is the smallest form of matter & 2 or more different atoms chemically bonded make compounds__ c. physical property & chemical property __Physical property can be observed w/o changing the compound, Chemical property can only be observed upon reaction___ d. mixture & pure substance __A mixture is multiple substances physically mixed where a pure substance is simply one substance___ e. physical change & chemical change __A physical change is the change in appearance but not chemical make up where chemical change is the change of a substance chemically to make a new substance ____________ 19. Using circles to represent particles, draw diagrams that illustrate the arrangements of particles in solids, liquids, and gases. 20. Explain how energy involved in chemical and physical change. In matter, solids have the lowest energy and slowest movement of particles and Gases have the highest energy and fastest movement of particles. So, the more energy put in, the faster the movement and the change of state occurs. For chemical change, energy is usually put off as in chemical reactions (exothermic) and sometimes taken in (endothermic). 21. Classify each as chemical change (cc) or physical change (pc): a. Ice melting __pc____________________ d. Paper burning __cc_________________ b. Metal rusting __cc__________________ e. Liquid evaporating __pc____________ c. Gas pressure increasing __pc______ f. Food digesting __cc__________________ 22. What is the difference between intensive and extensive properties? Intensive properties do not change when the amount of the substance changes (density, color, etc.), Extensive properties change when the amount changes (mass, volume, etc.) 23. Consider the burning of gasoline and the evaporation of gasoline. Which process represents a chemical change and which represents a physical change? Explain your answer. Gasoline burning produces new compounds (CO2 and H2O) meaning it is a chemical change. Evaporation of gasoline is a physical change because you still have gasoline; it is just changed state from liquid to vapor. 24. Describe the difference between a homogenous mixture and a heterogeneous mixture and give an example of each. An example of a homogeneous mixture is a cup of coffee where it is the same throughout. An example of a heterogeneous mixture would be a chocolate chip cookie where you can see different chips and cookie areas (Every bite is not the same). .
Recommended publications
  • Physical Changes, Chemical Changes, and How to Tell the Difference

    Physical Changes, Chemical Changes, and How to Tell the Difference

    LIVE INTERACTIVE LEARNING @ YOUR DESKTOP Physical Changes, Chemical Changes, and How to Tell the Difference Presented by: Adam Boyd December 5, 2012 6:30 p.m. – 8:00 p.m. Eastern time 1 Introducing today’s presenter… Adam Boyd Senior Education Associate Office of K–8 Science American Chemical Society 2 American Chemical Society Physical Changes, Chemical Changes, and How to Tell the Difference Adam M. Boyd Education Division American Chemical Society Our Goals Inquiry Based Activities – Clues of chemical change How to Science Background distinguish? – Chemical and Physical Properties – Chemical and Physical Change American Chemical Society 4 IYC Kits www.acs.org/iyckit American Chemical Society 5 IYC Kit Lesson Components 1. Lesson Summary 1 2. Key Concepts 3. Safety 2 4. The chemistry continues 5. Scientist introduction 6. Teacher demonstration(s) 3 7. Student activity Student activity sheet 8. Class discussion 9. Teacher demonstration 10. Application 4 American Chemical Society 6 IYC Kit Classic clues of chemical change? American Chemical Society 7 IYC Kit 1. Production of a gas Classic clues of chemical change? American Chemical Society 8 IYC Kit 1. Production of a gas Classic clues of chemical change? 2. Color change American Chemical Society 9 IYC Kit 1. Production of a gas Classic clues of chemical change? 2. Color change 3. Formation of a precipitate American Chemical Society 10 IYC Kit 1. Production of a gas Classic clues of chemical change? 2. Color change 3. Formation of a precipitate 4. Temperature change American Chemical Society 11 Chemical change or Physical change? Chemical change or Physical change? Chemical Change Physical Change IYC Kit 1.
  • Phase Transitions in Multicomponent Systems

    Phase Transitions in Multicomponent Systems

    Physics 127b: Statistical Mechanics Phase Transitions in Multicomponent Systems The Gibbs Phase Rule Consider a system with n components (different types of molecules) with r phases in equilibrium. The state of each phase is defined by P,T and then (n − 1) concentration variables in each phase. The phase equilibrium at given P,T is defined by the equality of n chemical potentials between the r phases. Thus there are n(r − 1) constraints on (n − 1)r + 2 variables. This gives the Gibbs phase rule for the number of degrees of freedom f f = 2 + n − r A Simple Model of a Binary Mixture Consider a condensed phase (liquid or solid). As an estimate of the coordination number (number of nearest neighbors) think of a cubic arrangement in d dimensions giving a coordination number 2d. Suppose there are a total of N molecules, with fraction xB of type B and xA = 1 − xB of type A. In the mixture we assume a completely random arrangement of A and B. We just consider “bond” contributions to the internal energy U, given by εAA for A − A nearest neighbors, εBB for B − B nearest neighbors, and εAB for A − B nearest neighbors. We neglect other contributions to the internal energy (or suppose them unchanged between phases, etc.). Simple counting gives the internal energy of the mixture 2 2 U = Nd(xAεAA + 2xAxBεAB + xBεBB) = Nd{εAA(1 − xB) + εBBxB + [εAB − (εAA + εBB)/2]2xB(1 − xB)} The first two terms in the second expression are just the internal energy of the unmixed A and B, and so the second term, depending on εmix = εAB − (εAA + εBB)/2 can be though of as the energy of mixing.
  • Grade 6 Science Mechanical Mixtures Suspensions

    Grade 6 Science Mechanical Mixtures Suspensions

    Grade 6 Science Week of November 16 – November 20 Heterogeneous Mixtures Mechanical Mixtures Mechanical mixtures have two or more particle types that are not mixed evenly and can be seen as different kinds of matter in the mixture. Obvious examples of mechanical mixtures are chocolate chip cookies, granola and pepperoni pizza. Less obvious examples might be beach sand (various minerals, shells, bacteria, plankton, seaweed and much more) or concrete (sand gravel, cement, water). Mechanical mixtures are all around you all the time. Can you identify any more right now? Suspensions Suspensions are mixtures that have solid or liquid particles scattered around in a liquid or gas. Common examples of suspensions are raw milk, salad dressing, fresh squeezed orange juice and muddy water. If left undisturbed the solids or liquids that are in the suspension may settle out and form layers. You may have seen this layering in salad dressing that you need to shake up before using them. After a rain fall the more dense particles in a mud puddle may settle to the bottom. Milk that is fresh from the cow will naturally separate with the cream rising to the top. Homogenization breaks up the fat molecules of the cream into particles small enough to stay suspended and this stable mixture is now a colloid. We will look at colloids next. Solution, Suspension, and Colloid: https://youtu.be/XEAiLm2zuvc Colloids Colloids: https://youtu.be/MPortFIqgbo Colloids are two phase mixtures. Having two phases means colloids have particles of a solid, liquid or gas dispersed in a continuous phase of another solid, liquid, or gas.
  • Introduction to Phase Diagrams*

    Introduction to Phase Diagrams*

    ASM Handbook, Volume 3, Alloy Phase Diagrams Copyright # 2016 ASM InternationalW H. Okamoto, M.E. Schlesinger and E.M. Mueller, editors All rights reserved asminternational.org Introduction to Phase Diagrams* IN MATERIALS SCIENCE, a phase is a a system with varying composition of two com- Nevertheless, phase diagrams are instrumental physically homogeneous state of matter with a ponents. While other extensive and intensive in predicting phase transformations and their given chemical composition and arrangement properties influence the phase structure, materi- resulting microstructures. True equilibrium is, of atoms. The simplest examples are the three als scientists typically hold these properties con- of course, rarely attained by metals and alloys states of matter (solid, liquid, or gas) of a pure stant for practical ease of use and interpretation. in the course of ordinary manufacture and appli- element. The solid, liquid, and gas states of a Phase diagrams are usually constructed with a cation. Rates of heating and cooling are usually pure element obviously have the same chemical constant pressure of one atmosphere. too fast, times of heat treatment too short, and composition, but each phase is obviously distinct Phase diagrams are useful graphical representa- phase changes too sluggish for the ultimate equi- physically due to differences in the bonding and tions that show the phases in equilibrium present librium state to be reached. However, any change arrangement of atoms. in the system at various specified compositions, that does occur must constitute an adjustment Some pure elements (such as iron and tita- temperatures, and pressures. It should be recog- toward equilibrium. Hence, the direction of nium) are also allotropic, which means that the nized that phase diagrams represent equilibrium change can be ascertained from the phase dia- crystal structure of the solid phase changes with conditions for an alloy, which means that very gram, and a wealth of experience is available to temperature and pressure.
  • Gp-Cpc-01 Units – Composition – Basic Ideas

    Gp-Cpc-01 Units – Composition – Basic Ideas

    GP-CPC-01 UNITS – BASIC IDEAS – COMPOSITION 11-06-2020 Prof.G.Prabhakar Chem Engg, SVU GP-CPC-01 UNITS – CONVERSION (1) ➢ A two term system is followed. A base unit is chosen and the number of base units that represent the quantity is added ahead of the base unit. Number Base unit Eg : 2 kg, 4 meters , 60 seconds ➢ Manipulations Possible : • If the nature & base unit are the same, direct addition / subtraction is permitted 2 m + 4 m = 6m ; 5 kg – 2.5 kg = 2.5 kg • If the nature is the same but the base unit is different , say, 1 m + 10 c m both m and the cm are length units but do not represent identical quantity, Equivalence considered 2 options are available. 1 m is equivalent to 100 cm So, 100 cm + 10 cm = 110 cm 0.01 m is equivalent to 1 cm 1 m + 10 (0.01) m = 1. 1 m • If the nature of the quantity is different, addition / subtraction is NOT possible. Factors used to check equivalence are known as Conversion Factors. GP-CPC-01 UNITS – CONVERSION (2) • For multiplication / division, there are no such restrictions. They give rise to a set called derived units Even if there is divergence in the nature, multiplication / division can be carried out. Eg : Velocity ( length divided by time ) Mass flow rate (Mass divided by time) Mass Flux ( Mass divided by area (Length 2) – time). Force (Mass * Acceleration = Mass * Length / time 2) In derived units, each unit is to be individually converted to suit the requirement Density = 500 kg / m3 .
  • Partition Coefficients in Mixed Surfactant Systems

    Partition Coefficients in Mixed Surfactant Systems

    Partition coefficients in mixed surfactant systems Application of multicomponent surfactant solutions in separation processes Vom Promotionsausschuss der Technischen Universität Hamburg-Harburg zur Erlangung des akademischen Grades Doktor-Ingenieur genehmigte Dissertation von Tanja Mehling aus Lohr am Main 2013 Gutachter 1. Gutachterin: Prof. Dr.-Ing. Irina Smirnova 2. Gutachterin: Prof. Dr. Gabriele Sadowski Prüfungsausschussvorsitzender Prof. Dr. Raimund Horn Tag der mündlichen Prüfung 20. Dezember 2013 ISBN 978-3-86247-433-2 URN urn:nbn:de:gbv:830-tubdok-12592 Danksagung Diese Arbeit entstand im Rahmen meiner Tätigkeit als wissenschaftliche Mitarbeiterin am Institut für Thermische Verfahrenstechnik an der TU Hamburg-Harburg. Diese Zeit wird mir immer in guter Erinnerung bleiben. Deshalb möchte ich ganz besonders Frau Professor Dr. Irina Smirnova für die unermüdliche Unterstützung danken. Vielen Dank für das entgegengebrachte Vertrauen, die stets offene Tür, die gute Atmosphäre und die angenehme Zusammenarbeit in Erlangen und in Hamburg. Frau Professor Dr. Gabriele Sadowski danke ich für das Interesse an der Arbeit und die Begutachtung der Dissertation, Herrn Professor Horn für die freundliche Übernahme des Prüfungsvorsitzes. Weiterhin geht mein Dank an das Nestlé Research Center, Lausanne, im Besonderen an Herrn Dr. Ulrich Bobe für die ausgezeichnete Zusammenarbeit und der Bereitstellung von LPC. Den Studenten, die im Rahmen ihrer Abschlussarbeit einen wertvollen Beitrag zu dieser Arbeit geleistet haben, möchte ich herzlichst danken. Für den außergewöhnlichen Einsatz und die angenehme Zusammenarbeit bedanke ich mich besonders bei Linda Kloß, Annette Zewuhn, Dierk Claus, Pierre Bräuer, Heike Mushardt, Zaineb Doggaz und Vanya Omaynikova. Für die freundliche Arbeitsatmosphäre, erfrischenden Kaffeepausen und hilfreichen Gespräche am Institut danke ich meinen Kollegen Carlos, Carsten, Christian, Mohammad, Krishan, Pavel, Raman, René und Sucre.
  • 42 the Reaction Between Zinc and Copper Oxide

    42 the Reaction Between Zinc and Copper Oxide

    The reaction between zinc and copper oxide 42 In this experiment copper(II) oxide and zinc metal are reacted together. The reaction is exothermic and the products can be clearly identified. The experiment illustrates the difference in reactivity between zinc and copper and hence the idea of competition reactions. Lesson organisation This is best done as a demonstration. The reaction itself takes only three or four minutes but the class will almost certainly want to see it a second time. The necessary preparation can usefully be accompanied by a question and answer session. The zinc and copper oxide can be weighed out beforehand but should be mixed in front of the class. If a video camera is available, linked to a TV screen, the ‘action’ can be made more dramatic. Apparatus and chemicals Eye protection Bunsen burner • Heat resistant mat Tin lid Beaker (100 cm3) Circuit tester (battery, bulb and leads) (Optional) Safety screens (Optional) Test-tubes, 2 (Optional – see Procedure g) Test-tube rack Access to a balance weighing to the nearest 0.1 g The quantities given are for one demonstration. Copper(II) oxide powder (Harmful, Dangerous for the environment), 4 g Zinc powder (Highly flammable, Dangerous for the environment), 1.6 g Dilute hydrochloric acid, approx. 2 mol dm-3 (Irritant), 20 cm3 Zinc oxide (Dangerous for the environment), a few grams Copper powder (Low hazard), a few grams. Concentrated nitric acid (Corrosive, Oxidising), 5 cm3 (Optional – see Procedure g) Technical notes Copper(II) oxide (Harmful, Dangerous for the environment) Refer to CLEAPSS® Hazcard 26. Zinc powder (Highly flammable, Dangerous for the environment) Refer to CLEAPSS® Hazcard 107 Dilute hydrochloric acid (Irritant at concentration used) Refer to CLEAPSS® Hazcard 47A and Recipe Card 31 Concentrated nitric acid (Corrosive, Oxidising) Refer to CLEAPSS® Hazcard 67 Copper powder (Low hazard) Refer to CLEAPSS® Hazcard 26 Zinc oxide (Dangerous for the environment) Refer to CLEAPSS® Hazcard 108.
  • Changes: Physical Or Chemical? by Cindy Grigg

    Changes: Physical Or Chemical? by Cindy Grigg

    Changes: Physical or Chemical? By Cindy Grigg 1 If you have studied atoms, you know that atoms are the building blocks of matter. Atoms are so small they cannot be seen with an ordinary microscope. Yet atoms make up everything in the universe. Atoms can combine with different atoms and make new substances. Substances can also break apart into separate atoms. These changes are called chemical changes or reactions. Chemical reactions happen when atoms gain, lose, or share electrons. What about when water freezes into ice? Do you think that's a chemical change? 2 When water freezes, it has changed states. You probably already know about the four states of matter. They are solid, liquid, gas, and plasma. Plasma is the fourth state of matter and is the most common state in the universe. However, it is rarely found on Earth. Plasma occurs as ball lightning and in stars. Water is a common substance that everyone has seen in its three states of matter. Water in its solid state is called ice. Water in the liquid state is just called water. Water as a gas is called water vapor. We can easily cause water to change states by changing its temperature. Water will freeze at 32 degrees Fahrenheit (0 Celsius). However, no chemical change has occurred. The atoms have not combined or broken apart to make a different substance; it is still water or H2O. When we heat water to a temperature of 212 F. or 100 Celsius, it will change into a gas called water vapor. Changes in states of matter are just physical changes.
  • Ways to Physically Separate a Mixture There Are 2 Types of Mixtures

    Ways to Physically Separate a Mixture There Are 2 Types of Mixtures

    Mixtures 12 Mixtures Homogenous Compare Heterogeneous compounds and Suspension Mixtures. Colloid Solution Differentiate Solute/Solvent between solutions, suspensions, and colloids Comparing Mixtures and Compounds Mixtures Compounds Made of 2 or more substances Made of 2 or more substances physically combined chemically combined Substances keep their own properties Substances lose their own properties Can be separated by physical means Can be separated only by chemical means Have no definite chemical composition Have a definite chemical composition What method is used to separate mixtures Ways to physically separate a Mixture based on boiling • Distillation – uses boiling point point? • Magnet – uses magnetism What method is used • Centrifuge – uses density to separate mixtures based on density? • Filtering – separates large particles from smaller ones What method is used There are 2 types of mixtures: to separate mixtures (1) Heterogeneous Mixtures: the parts mixed together can still be based on particle size? distinguished from one another...NOT uniform in composition Give examples of a heterogeneous Examples: chicken soup, fruit salad, dirt, sand in water mixture Mixtures 12 (2) Homogenous Mixtures: the parts mixed together cannot be distinguished from one another...completely uniform in composition. Give examples of a homogenous Examples: Air, Kool-aid, Brass, salt water, milk mixture Differentiate Types of Homogenous mixtures between a homogenous 1. Suspensions mixture and a i.e. chocolate milk, muddy water, Italian dressing heterogeneous mixture. They are cloudy (usually a liquid mixed with small solid particles) Identify an example of a suspension. Needs to be shaken or stirred to keep the solids from Will the solid settling particles settle in a suspension? The solids can be filtered out 2.
  • Solving Mixture and Solution Verbal Problems

    Solving Mixture and Solution Verbal Problems

    SOLVING SOLUTION AND MIXTURE VERBAL PROBLEMS This type of problem involves mixing two different solutions of a certain ingredient to get a desired concentration of the ingredient. Before we can solve problems that involve concentrations, we must review certain concepts about percents. If you need to do this, go to the brush-up materials for solving percent problems on the Dolciani website. 1. Solution Problems Basic Equation: amount of solution concentration of substance = amount of substance Example: 40 ounces (amount of solution) of a 25% solution of acid (concentration) contains 25(40) = 10 ounces of acid Usual equation to solve for the variable: Amount of substance in solution 1 + Amount of substance in solution 2 = Amount of substance in solution 2. Mixture Problems Basic Equation: unit price # units = cost (or value) Example: 5 pounds of apples (# units) that sell for $1.20 per pound (unit price) costs 5(1.20) = $6 Using equation to solve for the variable: Cost of ingredient 1 + Cost of ingredient 2 = Cost of mixture Now let’s look at an actual mixture problem. It is easiest when solving a mixture problem to make a table to get the information organized. No matter the story line of the problem, the table can be used and labelled as necessary. Let’s look at a few examples. Example 1: Fatima’s chemistry lab stocks an 8% acid solution and a 20% acid solution. How many ounces of each must she combine to produce 60 ounces of a mixture that is 10% acid? Solution: We want to find how much of each solution must be in the mixture.
  • Mixtures Are a Combination 3.1 of Two Or More Substances MIXTURES

    Mixtures Are a Combination 3.1 of Two Or More Substances MIXTURES

    Mixtures are a combination 3.1 of two or more substances MIXTURES A solution is a solute dissolved 3.2 in a solvent Mixtures can be separated according 3.3 to their physical properties 3.4 Mixtures can be separated according 3 to their size and mass What if? The different boiling points of liquids Case mix 3.5 can be used to separate mixtures What you need: a variety of different pencil cases (size, shape, colour) What to do: 1 Place all the pencil cases in Solubility can be used to one pile. 3.6 separate mixtures 2 List your pencil case’s properties that will allow it to DRAFT be identified easily (e.g. colour, shape, size and weight). 3 Give the list to another student. Can they identify your case by Waste water is a mixture that using the list? 3.7 can be separated What if? » What if you were blindfolded? Could you still find your pencil case? » What if the pencil cases were too small to feel? How could Materials recovery facilities you identify yours? 3.8 separate mixtures » What if all the pencil cases were exactly the same? Would it still be a mixture? Mixtures are a 3.1 combination of two or more substances Consider the things around you. Perhaps they are made of wood, glass or plastic. Wood, glass and plastic are all mixtures – each of these materials is made up of two or more substances. Some materials are pure substances. A pure substance is one where all the particles are identical.
  • Classification of Matter Section ●1 Composition of Matter

    Classification of Matter Section ●1 Composition of Matter

    266_277_Ch15_RE_896315.qxd 3/23/10 3:04 AM Page 266 S-034 113:GO00492:GPS_Reading_Essentials_SE%0:XXXXXXXXXXXXX_SE:Application_Files_ chapter 15 Classification of Matter section ●1 Composition of Matter What You’ll Learn Before You Read ■ what substances and mixtures are Matter is all around you. You breathe matter, sit on it, and ■ how to identify drink it every day. What words would you use to describe elements and different kinds of matter? compounds ■ the difference between solutions, colloids, and suspensions Read to Learn Underline Look for different descriptions of matter Pure Substances as you read each paragraph. Underline these descriptions. Have you ever seen a print that looked like a real painting? Read the underlined descriptions Did you have to touch it to find out? The smooth or rough again after you’ve finished surface told you whether it was a painting or a print. Each reading the section. material has its own properties. The properties of materials can be used to classify them into categories. Each material is made of a pure substance or of a mix of substances. A substance is a type of matter that is always made of the same material or materials. A substance can be either an element or a compound. Some substances you might recognize are helium, aluminum, water, and salt. What are elements? All substances are made of atoms. A substance is an element if all the atoms in the substance are the same. The graphite in your pencil is an element. The copper coating on most pennies is an element, too.