atoms, bonds, and molecules what is “stuff” made of?

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Atoms, Bonds, and Molecules What is “stuff” made of?. Atoms and Bonds I. Atoms A. Matter     1. ‘Elemental’ forms of matter, or ‘the elements’, are different forms of matter which have different chemical and physical properties, and can not be broken down further by chemical reactions. - PowerPoint PPT Presentation

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  • Atoms, Bonds, and Molecules

    What is stuff made of?

  • Atoms and BondsI. Atoms A. Matter 1. Elemental forms of matter, or the elements, are different forms of matter which have different chemical and physical properties, and can not be broken down further by chemical reactions.

  • Atoms and BondsI. Atoms A. Matter 1. Elemental forms of matter, or the elements, are different forms of matter which have different chemical and physical properties, and can not be broken down further by chemical reactions. There are 92 naturally occurring elements

  • Atoms and BondsI. Atoms A. Matter 1. Elements are different forms of matter which have different chemical and physical properties, and can not be broken down further by chemical reactions. 2. The smallest unit of an element that retains the properties of that element is an atom.

  • Atoms and BondsI. Atoms A. Matter 1. Elements are different forms of matter which have different chemical and physical properties, and can not be broken down further by chemical reactions. 2. The smallest unit of an element that retains the properties of that element is an atom. 3. Atoms are WICKED SMALL and are mostly SPACE. The material things in atoms are protons and neutrons in the nucleus, orbited by electrons: Proton: in nucleus; mass = 1, charge = +1 - Defines ElementNeutron: in nucleus; mass = 1, charge = 0Electron: orbits nucleus; mass ~ 0, charge = -1

    NOT TO SCALE

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms1. Subatomic Particles Proton: in nucleus; mass = 1, charge = +1 - Defines ElementNeutron: in nucleus; mass = 1, charge = 0Electron: orbits nucleus; mass ~ 0, charge = -1Orbit at quantum distances (shells)Shells 1, 2, and 3 have 1, 4, and 4 orbits (2 electrons each)Shells hold 2, 8, 8 electrons = distance related to energy

  • Neon (Bohr model)

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms1. Subatomic Particles2. Mass = protons + neutronsO815.99

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms1. Subatomic Particles2. Mass = protons + neutrons3. Charge = (# protons) - (# electrons)... If charge = 0, then you have an ...ION

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms4. Isotopes -

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms4. Isotopes - 'extra' neutrons... heavierSome are stableSome are not... they 'decay' - lose the neutronThese 'radioisotopes' emit energy (radiation)

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms4. Isotopes - 'extra' neutrons... heavierSome are stableSome are not... they 'decay' - lose protrons/neutronsThese 'radioisotopes' emit energy (radiation)

    So, K40, with 19 protons and 21 neutrons, decays to Ar40 (18 protons, 22 neutrons) with the conversion of a proton into a neutron. As neutrons weigh slightly less than protons, the mass that is lost in this conversion is lost as energy (E = mc2)

  • Atoms and BondsI. Atoms A. Matter B. Properties of Atoms4. Isotopes - 'extra' neutrons... heavierSome are stableSome are not... they 'decay' - lose the neutronThese 'radioisotopes' emit energy (radiation)This process is not affected by environmental conditions and is constant; so if we know the amount of parent and daughter isotope, and we know the decay rate, we can calculate the time it has taken for this much daughter isotope to be produced.

  • Atoms and BondsI. AtomsII. Bonds A. Molecules

  • Atoms and BondsI. AtomsII. Bonds A. Molecules 1. atoms chemically react with one another and form molecules - the atoms are "bound" to one another by chemical bonds - interactions among electrons or charged particles.

  • Atoms and BondsI. AtomsII. Bonds A. Molecules 1. atoms chemically react with one another and form molecules - the atoms are "bound" to one another by chemical bonds - interactions among electrons or charged particles. 2. Bonds form because atoms attain a more stable energy state if their outermost shell is full. It can do this by loosing, gaining, or sharing electrons. This is often called the 'octet rule' because the 2nd and 3rd shells can contain 8 electrons.

  • Atoms and BondsI. AtomsII. Bonds A. Molecules B. Covalent Bonds - atoms are shared

  • Atoms and BondsI. AtomsII. Bonds A. Molecules B. Covalent Bonds - atoms are shared C. Ionic Bond - transfer of electron and attraction between ionsClNa

  • Atoms and BondsI. AtomsII. Bonds A. Molecules B. Covalent Bonds - atoms are shared C. Ionic Bond - transfer of electron and attraction between ions D. Hydrogen Bonds - weak attraction between partially charged hydrogen atom in one molecule and a negative region of another molecule

  • D. Hydrogen Bonds - weak attraction between partially charged hydrogen atom in one molecule and a negative region of another molecule

  • D. Hydrogen Bonds - weak attraction between partially charged hydrogen atom in one molecule and a negative region of another molecule

  • D. Hydrogen Bonds - weak attraction between partially charged hydrogen atom in one molecule and a negative region of another molecule

  • Biologically Important Molecules

  • Biologically Important Molecules

    Water

  • Biologically Important Molecules

    WaterA. Structure - polar covalent bonds

  • Biologically Important Molecules

    WaterA. Structure - polar covalent bonds

  • Biologically Important Molecules

    WaterA. Structure - polar covalent bonds - partial charges

  • Biologically Important Molecules

    WaterA. Structure - polar covalent bonds - partial charges - hydrogen bonds

  • WaterA. StructureB. Properties - 1. cohesionwater sticks to itself through H-bonds

  • I. WaterB. Properties - 2. adhesionwater sticks to other charged surfaces

  • I. WaterB. Properties - consequences of cohesion/adhesionCapillary action rotating water water molecules stick to the inner surface of thin tubes, and act as a fulcrum for other water molecules that can spin and contact the surface above them through cohesion, those in contact with the new surface are themselves a surface for now water molecules to attach. - important in the mvmt of soil water up from the water table to the root zone, and up vascular plants in xylem tissue.

  • I. WaterB. Properties - 3. High specific heatspecific heat is the amount of energy change required to change the temperature of 1 g of that substance 1oC. By definition, a calorie is a change in heat energy needed to change 1ml (or g) of water 1oC. (Dietary calories are usually kilocalories).

  • I. WaterB. Properties - 3. High specific heatspecific heat is the amount of energy change required to change the temperature of 1 g of that substance 1oC. By definition, a calorie is a change in heat energy needed to change 1ml (or g) of water 1oC. (Dietary calories are usually kilocalories).

    Water has a high specific heat because of the hydrogen bonds, which must be broken before the molecules can move faster (increase temperature).

  • I. WaterB. Properties - consequences of waters high specific heatWater is an excellent thermal buffer - aqueous solutions change temperature more slowly than air (less dense aqueous solution).

  • I. WaterB. Properties - consequences of waters high specific heatWater is an excellent thermal buffer - aqueous solutions change temperature more slowly than air (less dense aqueous solution).

    So, aqueous environments are more thermally stable (air temps vary more dramatically than water temps)

  • I. WaterB. Properties - consequences of waters high specific heatWater is an excellent thermal buffer - aqueous solutions change temperature more slowly than air (less dense aqueous solution).

    So, aqueous environments are more thermally stable (air temps vary more dramatically than water temps)

    So, terrestrial organisms change temperature more slowly than the environment, giving them time to adjust behaviorally (like leaving!)

  • I. WaterB. Properties - 4. High heat of vaporizationQuantity of heat a liquid must absorb for 1 g of it to change to a gas.

    Waters high heat of vaporization means that: - water doesnt change state quickly; it can absorb a lot of energy without changing state.

  • I. WaterB. Properties - 4. High heat of vaporizationQuantity of heat a liquid must absorb for 1 g of it to change to a gas.

    Waters high heat of vaporization means that: - water doesnt change state quickly; it can absorb a lot of energy without changing state. - when it does change state, the most energetic molecules evaporate and leave the liquid (or surface); so the average kinetic energy (temperature) of the liquid or surface drops dramatically this is evaporative cooling.

  • I. WaterB. Properties - 4. High heat of vaporizationQuantity of heat a liquid must absorb for 1 g of it to change to a gas.

    Waters high heat of vaporization means that: - water doesnt change state quickly; it can absorb a lot of energy without changing state. - when it does change state, the most energetic molecules evaporate and leave the liquid (or surface); so the average kinetic energy (temperature) of the liquid or surface drops dramatically this is evaporative cooling. - evaporative cooling keeps water bodies cooler than air, and cools living organisms (evapotranspiration, perspiration).

  • I. WaterB. Properties - 6. solventIonic and polar compounds dissolve in water Salts dissolve in water when their constituent ions separate and bond to water molecules instead of each other.

  • I. WaterB. Properties -

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