* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Chapter 3
Survey
Document related concepts
Metastable inner-shell molecular state wikipedia , lookup
Homoaromaticity wikipedia , lookup
Physical organic chemistry wikipedia , lookup
State of matter wikipedia , lookup
Isotopic labeling wikipedia , lookup
Aromaticity wikipedia , lookup
Electron configuration wikipedia , lookup
Ionic compound wikipedia , lookup
Acid–base reaction wikipedia , lookup
Electrochemistry wikipedia , lookup
Rutherford backscattering spectrometry wikipedia , lookup
Electrolysis of water wikipedia , lookup
Transcript
Chapter 2 The Chemistry of Life The Chemistry of Life • Matter- anything that has mass and takes up space – Solid: any substance that has a definite shape and a definite volume – Liquid: has a definite volume but no definite shape – Gas: has no definite volume or shape *Changing states requires adding or removing energy Physical Changes • A physical change is a change in the size, shape, or state of a substance – Ex: melting, freezing, molding clay, cutting wood Atoms • Atoms- the smallest particles that make up all matter – Protons(+): positively charged particles found in the nucleus of an atom – Neutrons(o): neutral particles found in the nucleus of an atom – Electrons(-): negatively charged particles found outside of the nucleus Model of the Atom Elements • Elements are substances made of only one type of atom – Ex: O2(oxygen) H2(hydrogen) O3(ozone) Ions • Ions are atoms that have lost or gained electrons • Ions have a positive(+) or negative(-) charge Lose Na Electron Na + Positive ion _ Gain Cl Electron Cl Negative ion Compounds & Molecules • Compounds and Molecules are formed when 2 or more different elements are bonded together • Ex: Compound- Salt(NaCl) Molecule- Water(H2O) Molecular Formulas • Molecular formulas show the kind and # of atoms in a molecule – H2O = 2 hydrogen atoms + 1 oxygen atom – CO2 = 1 carbon atom + 2 oxygen atoms – C6H12O6 = 6 carbon atoms + 12 hydrogen atoms + 6 oxygen atoms – NaCl = 1 sodium ion(Na) + 1 chlorine ion(Cl) Chemical Change • Chemical change occurs when atoms combine or separate to create new substances • Chemical changes use or give off energy • Ex: Combustion(burning) C3H8 + O2 CO2 + H2O propane + oxygen carbon dioxide + water • Ex: Oxidation(rusting) Fe + O2 Fe2O3 iron + oxygen ironoxide(rust) Mixtures • A mixture forms when chemicals combine but do not bond – Ex: salt water, salad dressing, chocolate milk • Solutions: is a mixture with it’s parts evenly mixed Solute – substance that gets dissolved ex: salt, sugar, chocolate Solvent – substance that dissolves another substance ex: water, milk, alcohol Bonding • Bonding is a force of attraction holding atoms together • Types of Bonding: – Covalent Bonds – Ionic Bonds – Hydrogen Bonds Covalent Bonds • Covalent bonds form when 2 or more neutral atoms share electrons to form a molecule – Ex: H2O(water) -Ex: CO2(carbon dioxide) Ionic Bonds • Ionic bonds form when 2 or more ions become held together by their opposite charges • Ex: NaCl(salt) – Positive ions are attracted to negative ions Hydrogen Bonds • Hydrogen bonds hold together water molecules Cohesion & Adhesion • Cohesion- the attraction between molecules of the same kind – Ex: water forms droplets, surface tension • Adhesion- the attraction between different substances – Ex: water drops stick to leaves and skin Cohesion & Adhesion Acids & Bases • Acids- contain large amounts of hydrogen(H+) ions – Acids turn pH paper RED Ex: stomach acid(HCl), vinegar, citric acid • Bases- contain large amounts of hydroxide(OH-) ions – Bases turn pH paper BLUE Ex: bleach, ammonia, soap Neutral Substances • Neutral substances have equal amounts of hydrogen(H+) and hydroxide(OH-) ions Ex: water (H2O), alcohol (C2H5OH), oil - neutral substances do not change pH paper Types of Compounds • Inorganic- come from non-living things, do not contain carbon Ex: Salt (NaCl) – sodium chloride Water (H2O) • Organic- come from living things and contain carbon Ex: Carbohydrates, Fats, Proteins, Nucleic Acids Carbohydrates • Used for Short Term energy • Contain: carbon(C), Hydrogen(H), oxygen(O) • Ex: sugars- glucose, sucrose, fructose starches- bread, pasta, potatoes Glucose - C6H12O6 Fats & Lipids • Used for Long Term energy storage • Contain: carbon(C), hydrogen(H), oxygen(O) • Ex: fats, oils, waxes Proteins • Used to Build and Repair body tissues • Contain: carbon(C), hydrogen(H), oxygen(O), & nitrogen(N) • Proteins are made from amino acids Nucleic Acids • Used to make DNA • Contain: carbon(C), hydrogen(H), oxygen(O), nitrogen(N), & phosphorus(P) Enzymes • Enzymes are a special type of protein used to perform chemical reactions within the body • Certain enzymes build new molecules and others break down molecules within the body Enzymes • Enzymes bind to a substrate with a matching active site END OF CHAPTER 2 NOTES!!!