SCIENCE Assessment ReviewSCIENCE Assessment Review555SCIENCE Assessment ReviewSCIENCE Assessment Review555555SCIENCE Assessment ReviewSCIENCE CIENCE Assessment ssessment RevieweviewCopyright © NewPath Learning. All rights reserved.www.newpathlearning.comCHARTSCHARTSGRADEGRADE888\|xiBAHBDy01210ozX34-8901STAARMATTER & ENERGYMATTER & ENERGYSturdy, Free-Standing Design, Perfect for Learning Centers!Reverse Side Features Questions, Labeling Exercises, Vocabulary Review & more!Curriculum Mastery® Flip Charts Combine Essential STAAR Science Knowledge & Skills with Hands-On Review!Phone: 800-507-0966 • Fax: 800-507-0967 www.newpathlearning.com NewPath Learning® products are developed by teachers using research-based principles and are classroom tested. The company’s product line consists of an array of proprietary curriculum review games, workbooks, posters and other print materials. All products are supplemented with web-based activities, assessments and content to provide an engaging means of educating students on key, curriculum-based topics correlated to applicable state and national education standards. Copyright © 2018 NewPath Learning. All Rights Reserved. Printed in the United States of America. Curriculum Mastery® and NewPath Learning® are registered trademarks of NewPath Learning LLC. Science Curriculum Mastery® Flip Charts provide comprehensive coverage of essential STARR science concepts in an illustrated format that is visually appealing, engaging and easy to use. Curriculum Mastery® Flip Charts can be used with the entire classroom, with small groups or by students working independently. HOW TO USE Classroom Use Each Curriculum Mastery® Flip Chart can be used to graphically introduce or review a topic of interest. Side 1 of each Flip Chart provides graphical representation of key concepts in a concise, grade appropriate reading level for instructing students. The reverse Side 2 of each Flip Chart allows teachers or students to summarize key concepts and assess their understanding. Note: Be sure to use an appropriate dry-erase marker and to test it on a small section of the chart prior to using it. The Activity Guide included provides a black-line master of each Flip Chart which students can use to fill in before, during, or after instruction. While the activities in the guide can be used in conjunction with the Flip Charts, they can also be used individually for review or as a form of assessment or in conjunction with any other related assignment. Learning Centers Each Flip Chart provides students with a quick illustrated view of science curriculum concepts. Students may use these Flip Charts in small group settings along with the corresponding activity pages contained in the guide to learn or review concepts already covered in class. Students may also use these charts as reference while playing the NewPath’s Curriculum Mastery® Games. Independent student use Students can use the hands-on Flip Charts to practice and learn independently by first studying Side 1 of the chart and then using Side 2 of the chart or the corresponding graphical activities contained in the Activity Guide. Reference/Teaching resource Curriculum Mastery® Charts are a great visual supplement to any curriculum or they can be used in conjunction with NewPath’s Curriculum Mastery® Games. STAAR - Grade 8 SCIENCE Assessment Review Flip Chart Matter and Energy The student will demonstrate an understanding of the properties of matter and energy and their interactions. Matter and energy. The student knows that matter is composed of atoms and has chemical and physical properties. The student is expected todetermine how matter is classified, changed, and used. The student is expected to (A) describe the structure of atoms, including the masses, electrical charges, and locations, of protons and neutrons in the nucleus and electrons in the electron cloud; Readiness Standard• Properties of Atoms(B) identify that protons determine an element’s identity and valence electrons determine its chemical properties, including reactivity; Readiness Standard• Atomic Configuration & Bonding(C) interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements; Readiness Standard• Elements & the Periodic Table(B) diagram the flow of energy through living systems, including food chains, food webs, and energy pyramids; Supporting Standard• Energy Pyramid7.5 Matter and energy. The student knows that interactions occur between matter and energy. Student is expected to6.6 Matter and energy. The student knows matter has physical properties that can be used for classification. The student is expected to(D) recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas containing subscripts; Readiness Standard(E) investigate how evidence of chemical reactions indicates that new substances with different properties are formed and how that relates to the law of conservation of mass; Readiness Standard• Formulas & Equations• Chemical Reactions(A) distinguish between physical and chemical changes in matter; Supporting Standard• Metals, Nonmetals & Metalloids(A) compare metals, nonmetals, and metalloids using physical properties such as luster, conductivity, or malleability; Supporting Standard• Classes of Elements 7.6 Matter and energy. The student knows that matter has physical and chemical properties and can undergo physical and chemical changes. The student is expected to(B) calculate density to identify an unknown substance; Supporting Standard• Measuring Matter Isotopes of CarbonElectron Dot DiagramHCOHHOHHONaClNa+ClCarbon-126 neutronsCarbon-137 neutronsCarbon-148 neutronsSodium atomHydrogenatomOxygenatomWatermoleculeChlorine atomIonic compound - sodium chloride (salt)Cl-Na+Crystal structure of salt (NaCl)ProtonNeutroncovalentbondsnucleusCarbon atomcloud of electronsThe AtomAtoms are the basic building blocks of matter that make up everything around us. A pencil, the air, even your body is made up of atoms! There are 90 naturally occurring kinds of atoms. Scientists in labs have been able to make about 25 more. An atom is the smallest part of an element that has all the properties of that element. Particles of an AtomThe modern atomic model, suggests that an atom has two particles in the nucleus, a proton which carries a positive charge and a neutron or neutrally charged particle. Surrounding the nucleus is an electron cloud with electrons which carry a negative charge, moving in various directions.The atomic mass number is the sum of the protons and neutrons in the nucleus of an atom. The number of protons is the atomic number of that atom.How Do Atoms Differ?Atoms of the same element can have different numbers of neutrons. Such atoms with the same number of protons and a different number of neutrons are called isotopes. For example, the three isotopes of Carbon have the same number of protons (or the same atomic number) and electrons but they differ in their number of neutrons and thus have a different atomic mass.Valence Electrons & BondingElectrons surrounding the nucleus are organized in energy levels. An electron that is in the outermost energy level of an atom is a valence electron. A valence electron determines an atom’s chemical properties and whether an atom will form bonds. A bond is the force that joins two atoms together forming a new substance.Ionic BondsAn ionic bond is formed when one or more valence electrons are transferred from one atom to another.Covalent BondsA covalent bond is formed when atoms share one or more pairs of electrons.An atom’s valence electrons are represented by dots placed around the symbol of an element.OHHtransfer ofelectronParticleProtonNeutronElectronp+ne-1+01-1111,836SymbolChargeParticles in an AtomRelativeMass (amu)ModelC6CarbonElement nameSymbolAtomic numberAtomic mass12© Copyright NewPath Learning. All Rights Reserved. 94-4803www.newpathlearning.comProperties of AtomsCarbon-12Carbon-13Carbon-14HHOHHOWatermoleculeNaClNa+ClIonic compound - sodium chloride (salt)Isotopes of Carbon\|xiBAHBDy01805mzVThe AtomWhat are atoms? _____________________________________________________________________________________________________________________________________________________________________________________________________Particles of an AtomThe modern atomic model, suggests that an atom has two particles in the ____________________, a ____________________ which carries a positive charge and a ____________________or neutrally charged particle. Surrounding the nucleus is an electron cloud with ____________________ which carry a ____________________ charge, moving in various directions.The ________________________________________ is the sum of the ____________________and ____________________in the nucleus of an atom.____________________________________ is the ___________________________ of that atom.How Do Atoms Differ?What are isotopes? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Valence Electrons and BondingElectrons surrounding the nucleus are organized in ____________________ ____________________ . An electron that is in the outermost energy level of an atom is a ____________________ ____________________ . A valence electron determines an atom’s ____________________ ____________________ and whether an atom will form ____________________ . A ____________________ is the force that joins two atoms together forming a new substance.Ionic BondsHow do ionic bonds form?_____________________________________________________________________________________________Covalent BondsHow do covalent bonds form?____________________________________________________________________________________Electron Dot DiagramHCOAn atom’s valence electrons are represented by dots placed around the symbol of an element.OHHC6Carbon12Key Vocabulary Terms• atom• atomic mass• atomic model• atomic number• charge• chemical bond• covalent bond• electron• electron cloud• element• energy level• ionic bond• isotope• negative charge• neutron• nucleus• particle• positive charge• proton• valence electronCarbon atomNumber of neutronsNumber of neutronsNumber of neutrons© Copyright NewPath Learning. All Rights Reserved. 94-4803www.newpathlearning.comProperties of AtomsAtomic Configuration & Bonding© Copyright NewPath Learning. All Rights Reserved. 94-4837Visit www.newpathlearning.com for Online Learning Resources.Electron ConfigurationThe specific way the electrons are arranged in an atom is called the electron configuration. Electrons play an important role in how elements interact with each other and form compounds. The electrons are distributed among orbital shells or energy levels (1, 2, 3 and so on) that are different distances from the nucleus. The larger the number of the energy level, the farther it is from the nucleus. Electrons that are in the highest or outmost energy level are called valence electrons. The valence electrons are the ones that are lost, gained or shared during chemical bonding. Oxygen atom (neutral)electronsorbital shell 1orbital shell 2atomic number = 8protons = 8electrons = 8electroncloudnucleusvalenceelectronvalenceshellBr35BromineCl17ChlorineF9FluorineI53IodineAt85AstatineLi3LithiumNa11SodiumK19PotassiumRb37RubidiumCs55CesiumAlkali metals• 1 valence electron• lose electronHalogens• 7 valence electrons• gain electronSodiumChlorineAluminumOxygenAtoms with 4 or more valence electronsgain electrons.Atoms with 3 or lessvalence electronslose electrons.Atoms with fullvalence shells will not combine with other elements.NeonElectron Dot DiagramThe number of valence electrons in an atom of an element determines many properties of that element, including the ways in which the atom can bond with other atoms. An electron dot diagram is often used to depict the valence electrons in an atom. Each atom of an element has a specific number of valence electrons, ranging from 1 to 8. The electron dot diagram includes the element symbol, surrounded by dots. Each dot represents 1 valence electron. The dots are spaced out above, below, to the left, and to the right of the symbol for the first 4 valence electrons. For atoms with greater than 4 valence electrons, the dots must be paired up. The dot diagrams for atoms can also be used to show the bond between different atoms in a molecule.COvalenceelectronsCarbonOxygenHe2HeliumNe10NeonAr18ArgonKr36KryptonXe54XenonRn86RadonArgonNeonKryptonNoble gases• 8 valence electronsStability of AtomsAtoms of most elements are more stable and are less likely to react with other atoms, when they have 8 valence electrons in their outer shell. For example, atoms of neon, argon, krypton, and xenon are very unreactive because they all have 8 valence electrons. Atoms usually react in a way that makes each atom more stable by losing, gaining, or sharing electrons in a chemical bond with other atoms.Valence Electrons & BondingThe outermost orbital shell, called the valence shell, is most often involved in chemical bonding. Elements in the same group in the periodic table have the same number of electrons in their valence shell. For example, all elements in group 1, alkali metals, have 1 valence electron. Group 1 atoms prefer to lose 1 electron to become stable. However, all elements in group 17, halogens, have 7 valence electrons. These atoms will gain 1 electron to fill their valence shell. Pause and ReviewFill in the table below. Group #CCuBeOXe # of electrons# of valenceelectronsElement(neutral)Use the information in the illustrations to answer the questions.NaFNeO1) Which element has 1 valence electron? ________________________________2) Which element is most reactive? ______________________________________3) Which element has a full valence shell? ________________________________4) Which element is the most stable? ____________________________________5) Which element has 6 valence electrons? _______________________________6) Which element has 7 valence electrons? _______________________________Atomic Configuration & Bonding© Copyright NewPath Learning. All Rights Reserved. 94-4837Visit www.newpathlearning.com for Online Learning Resources.HH11123456789101112131415161718234567HydrogenHe2HeliumNe10NeonAr18ArgonKr36KryptonXe54XenonRn86RadonBrHgHg35BromineCl17ChlorineF9FluorineO8OxygenN7NitrogenC6CarbonB5BoronLi3LithiumNa11SodiumK19PotassiumCa20CalciumRb37RubidiumCs55CesiumFr87FranciumRa88RadiumAc89ActiniumRf104RutherfordiumDb105DubniumSg106SeaborgiumBh107BohriumHs108HassiumMt109Meitnerium110Ununnilium111Unununium112UnunbiumUub114UnunquaterniumUuqUuuUunBa56BariumLa57LanthanumHf72HafniumTa73TantalumW74TungstunRe75RheniumOs76OsmiumIr77IridiumPt78PlatinumAu79Gold80MercuryTl81ThalliumPb82LeadBi8384BismuthPoPoloniumSr38StrontiumY39YttriumZr40ZirconiumNb41NiobiumMo42MolybdenumTcTc43TechnetiumRu44RutheniumRh45RhodiumPd46PalladiumAg47SilverCd48CadmiumIn49IndiumSn50TinSc21ScandiumTi22TitaniumV23VanadiumCr24ChromiumMn25ManganeseFe26IronCo27CobaltNiNi28NickelCu29CopperZn30ZincGa31GalliumAl13AluminumMg12MagnesiumBe4BeryliumSi14SiliconP15PhosphorusS16SulfurSe34SeleniumAs33ArsenicGe32GermaniumSb51 AntimonyTe52TelluriumI53IodineAt85AstatinecolumnLanthanidssolidliquidgasunknownmetalmetalloidnonmetalCe58CeriumTh90ThoriumPa91ProtactiniumPr59PraseodymiumNd60NeodymiumU92UraniumNp93NeptuniumPm61PromethiumSm62SamariumPu94PlutoniumAm95AmericiumEu63EuropiumGd64GadoliniumCm96CuriumBk97BerkeliumTb65TerbiumDy66DysprosiumCf98CaliforniumEs99EinsteiniumHo67HolmiumEr68ErbiumFm100FermiumMd101MendeleviumTm69ThuliumYb70YtterbiumLu71Lutetium No102NobeliumLr103LawrenciumActinidsChemical SymbolBackgroundH1HydrogenHe2HeliumNe10NeonAr18ArgonKr36KryptonXe54XenonRn86RadonBrHg35BromineCl17ChlorineF9FluorineO8OxygenN7NitrogenC6CarbonB5BoronLi3LithiumNa11SodiumK19PotassiumCa20CalciumRb37RubidiumCs55CesiumFr87FranciumRa88RadiumAc89ActiniumRf104RutherfordiumDb105DubniumSg106SeaborgiumBh107BohriumHs108HassiumMt109Meitnerium110Darmstadtium111Roentgenium112CoperniciumCn114FleroviumFl116LivermoriumLvRgDsBa56BariumLa57LanthanumHf72HafniumTa73TantalumW74TungstunRe75RheniumOs76OsmiumIr77IridiumPt78PlatinumAu79Gold80MercuryTl81ThalliumPb82LeadBi8384BismuthPoPoloniumSr38StrontiumY39YttriumZr40ZirconiumNb41NiobiumMo42MolybdenumTc43TechnetiumRu44RutheniumRh45RhodiumPd46PalladiumAg47SilverCd48CadmiumIn49IndiumSn50TinSc21ScandiumTi22TitaniumV23VanadiumCr24ChromiumMn25ManganeseFe26IronCo27CobaltNi28NickelCu29CopperZn30ZincGa31GalliumAl13AluminumMg12MagnesiumBe4BeryliumSi14SiliconP15PhosphorusS16SulfurSe34SeleniumAs33ArsenicGe32GermaniumSb51 AntimonyTe52TelluriumI53IodineAt85AstatineCe58CeriumTh90Pa91Pr59PraseodymiumNd60NeodymiumU92Np93Pm61PromethiumSm62SamariumPu94Am95Eu63EuropiumGd64GadoliniumCm96Bk97Tb65TerbiumDy66DysprosiumCf98Es99Ho67HolmiumEr68ErbiumFm100Md101Tm69ThuliumYb70YtterbiumLu71Lutetium No102Lr103ThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrencium© Copyright NewPath Learning. All Rights Reserved. 94-4804www.newpathlearning.comO8OxygenElement nameChemical SymbolAtomic numberAtomic mass16Periodic Table of the ElementsWhat are elements?Elements are the basic building blocks of matter. Each element is made up of one type of atom which determines its properties. Each element is represented by a chemical symbol. The Periodic Table groups elements in an organized fashion. Each element has its own unique symbol. Elements in each column have similar chemical properties. Elements in each row are arranged according to the number of protons. The number of protons (atomic number) increases from left to right in each row.Group 1: Alkali MetalsThese metals are very reactive which are only found in compounds.Group 2: Alkaline Earth MetalsThese metals are fairly reactive, conduct electricity and are only found in compounds. Magnesium and calcium are the two most common elements in this group.Group 3-12: Transition MetalsThese metals are less reactive than metals in Group 1 and 2. They are hard, shiny and good conductors of electricity. Elements such as zinc, cadmium and others in this group are used to make colorful paint compounds.The atomic mass number is the sum of the protons and neutrons in the nucleus of an atom.The number of protons is the atomic number of that atom.A period is a horizontal row of elementsA column of elements is known as a group or family.HydrogenHydrogen is set apart from the rest of the elements because of its unique properties. It is the most abundant element in our universe.Group 13: Boron GroupAluminum is the most common element is this group.Group 14: Carbon FamilyCarbon makes up compounds such as proteins, fats, and carbohydrates necessary for all life on Earth.Group 15: Nitrogen FamilyNitrogen makes up about 80% of the air in our atmosphere.Group 16: Oxygen FamilyOxygen makes up about 20% of the air in our atmosphere. It is necessary for most living things on Earth. Oxygen is also necessary for combustion of any substance.Group 17: HalogensHalogens are very reactive nonmetals which are only found in compounds.Group 18: Noble GasesNoble gases are unreactive nonmetals which are colorless and odorless at room temperature. Some of these gases are used to make “neon” lights.Earth’s AtmosphereperiodElements & the Periodic TableO8Oxygen16\|xiBAHBDy01802lz[HH11123456789101112131415161718234567HydrogenHe2HeliumNe10NeonAr18ArgonKr36KryptonXe54XenonRn86RadonBrHgHg35BromineCl17ChlorineF9FluorineO8OxygenN7NitrogenC6CarbonB5BoronLi3LithiumNa11SodiumK19PotassiumCa20CalciumRb37RubidiumCs55CesiumFr87FranciumRa88RadiumAc89ActiniumRf104RutherfordiumDb105DubniumSg106SeaborgiumBh107BohriumHs108HassiumMt109Meitnerium110Ununnilium111Unununium112UnunbiumUub114UnunquaterniumUuqUuuUunBa56BariumLa57LanthanumHf72HafniumTa73TantalumW74TungstunRe75RheniumOs76OsmiumIr77IridiumPt78PlatinumAu79Gold80MercuryTl81ThalliumPb82LeadBi8384BismuthPoPoloniumSr38StrontiumY39YttriumZr40ZirconiumNb41NiobiumMo42MolybdenumTcTc43TechnetiumRu44RutheniumRh45RhodiumPd46PalladiumAg47SilverCd48CadmiumIn49IndiumSn50TinSc21ScandiumTi22TitaniumV23VanadiumCr24ChromiumMn25ManganeseFe26IronCo27CobaltNiNi28NickelCu29CopperZn30ZincGa31GalliumAl13AluminumMg12MagnesiumBe4BeryliumSi14SiliconP15PhosphorusS16SulfurSe34SeleniumAs33ArsenicGe32GermaniumSb51 AntimonyTe52TelluriumI53IodineAt85AstatineLanthanidssolidliquidgasunknownmetalmetalloidnonmetalCe58CeriumTh90ThoriumPa91ProtactiniumPr59PraseodymiumNd60NeodymiumU92UraniumNp93NeptuniumPm61PromethiumSm62SamariumPu94PlutoniumAm95AmericiumEu63EuropiumGd64GadoliniumCm96CuriumBk97BerkeliumTb65TerbiumDy66DysprosiumCf98CaliforniumEs99EinsteiniumHo67HolmiumEr68ErbiumFm100FermiumMd101MendeleviumTm69ThuliumYb70YtterbiumLu71Lutetium No102NobeliumLr103ActinidsChemical SymbolBackgroundH1HydrogenHe2HeliumNe10NeonAr18ArgonKr36KryptonXe54XenonRn86RadonBrHg35BromineCl17ChlorineF9FluorineO8OxygenN7NitrogenC6CarbonB5BoronLi3LithiumNa11SodiumK19PotassiumCa20CalciumRb37RubidiumCs55CesiumFr87FranciumRa88RadiumAc89ActiniumRf104RutherfordiumDb105DubniumSg106SeaborgiumBh107BohriumHs108HassiumMt109Meitnerium110Darmstadtium111Roentgenium112CoperniciumCn114FleroviumFl116LivermoriumLvRgDsBa56BariumLa57LanthanumHf72HafniumTa73TantalumW74TungstunRe75RheniumOs76OsmiumIr77IridiumPt78PlatinumAu79Gold80MercuryTl81ThalliumPb82LeadBi8384BismuthPoPoloniumSr38StrontiumY39YttriumZr40ZirconiumNb41NiobiumMo42MolybdenumTc43TechnetiumRu44RutheniumRh45RhodiumPd46PalladiumAg47SilverCd48CadmiumIn49IndiumSn50TinSc21ScandiumTi22TitaniumV23VanadiumCr24ChromiumMn25ManganeseFe26IronCo27CobaltNi28NickelCu29CopperZn30ZincGa31GalliumAl13AluminumMg12MagnesiumBe4BeryliumSi14SiliconP15PhosphorusS16SulfurSe34SeleniumAs33ArsenicGe32GermaniumSb51 AntimonyTe52TelluriumI53IodineAt85AstatineCe58CeriumTh90Pa91Pr59PraseodymiumNd60NeodymiumU92Np93Pm61PromethiumSm62SamariumPu94Am95Eu63EuropiumGd64GadoliniumCm96Bk97Tb65TerbiumDy66DysprosiumCf98Es99Ho67HolmiumEr68ErbiumFm100Md101Tm69ThuliumYb70YtterbiumLu71Lutetium No102Lr103ThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrencium© Copyright NewPath Learning. All Rights Reserved. 94-4804www.newpathlearning.comPeriodic Table of the ElementsWhat are elements?____________________ are the basic building blocks of matter. Each element is made up of one type of _____________________ which determines its properties. Each element is represented by a _____________________ _____________________ . The _____________________ _____________________ groups elements in an organized fashion. Each element has its own unique _____________________. Elements in each _____________________ have similar chemical properties. Elements in each _____________________ are arranged according to the number of protons. The number of protons (atomic number) _____________________ from left to right in each row.Group 1: Alkali Metals_____________________________________________________________________________________________________________________Group 2: Alkaline Earth Metals_____________________________________________________________________________________________________________________Group 3-12: Transition Metals_____________________________________________________________________________________________________________________Hydrogen______________________________________________________________________________Group 13: Boron Group__________________________________________________________________________________________________________________Group 14: Carbon Family__________________________________________________________________________________________________________________Group 15: Nitrogen Family__________________________________________________________________________________________________________________Group 16: Oxygen Family__________________________________________________________________________________________________________________Group 17: Halogens__________________________________________________________________________________________________________________Group 18: Noble Gases__________________________________________________________________________________________________________________Key Vocabulary Terms•atomic mass•atomic number•chemical symbol•element•group•matter•neutron•period•protonThe atomic mass number is the sum of the ____________________ and ____________________ in the nucleus of an atom. The number of protons is the ____________________ ____________________ of that atom.A ____________________ is a horizontal row of elementsA column of elements is known as a ____________________ or ____________________ .Elements & the Periodic TableFormulas & Equations© Copyright NewPath Learning. All Rights Reserved. 94-4860Visit www.newpathlearning.com for Online Learning Resources.Chemical Formulas Chemical formulas are a shorthand way to represent the types of atoms and their numbers in an element or a compound. The atoms of each element are represented by one or two letters. Chemical EquationsA chemical reaction can be expressed as a chemical equation. A chemical equation is a statement of a chemical change using symbols. Consider the reaction between carbon and oxygen gas to form carbon dioxide. The starting substances, known as reactants, are carbon and oxygen gas. The final substance formed, known as a product, is carbon dioxide. To write the chemical equation for a reaction, first you write the symbols for the reactants, then an arrow, followed by the symbols for the products. The “plus” (+) sign separates the reactants or products from one another. The arrow indicates the direction of the reaction or “to yield.”chemical formulaH2O2 Hydrogen atoms1 Oxygen atomreactantsproductCarbonOxygen gasCarbon Dioxide++CO2CO2When more than one atom of a specific element is found in a molecule, a subscript is used to indicate this in the chemical formula. For example, the chemical formula for water, H2O, represents that two atoms of hydrogen have joined together with one atom of oxygen to form a molecule of water.CO2OCOsubscriptelementscompoundNext >