Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Unit 3 – Lecture 1 Levels of Organization The basic unit of living things is a cell , because all organisms are made of them. Cells, however, have smaller components…and cells make up larger structures that compose organisms [anything with all of the characteristics of life]. Levels of Organization – cont’d Atom Cell Molecule Tissue Biomolecule Organ [aka macro- molecule] Organelle Organ system Organism Discuss What are the three types of subatomic particles? [the three particles that make up an atom] What are their charges? Atoms atom - smallest part of an element that still has all of the element’s characteristics made of subatomic particles “sub-” – under, below, less than protons [p+] neutrons [n0] electrons [e-] Atoms – cont’d Types of Subatomic Particles [p+] – positively charged subatomic particle found in the nucleus of an atom [n0] – non-charged subatomic particle [neutral] found in the nucleus of an atom [e-] – negatively charged subatomic particle found outside of the nucleus in energy levels [aka e- clouds, e- shells, etc] Atoms – cont’d Elements are made of atoms. element – a pure chemical substance consisting of a singular type of atom. found on the periodic table in their neutral state • atomic number – p+ (also # e- bc neutral) • chemical symbol – name of element • atomic mass – mass of p+ plus mass of n0 Discuss The atomic # of an element represents what about the atom? The atomic mass of an element represents what about an atom? If looking at a periodic table, which is the larger # in each element box – the atomic #, or the atomic mass? What is the atomic mass of the elements to the right? Atoms – cont’d Sometimes, however, elements can also contain different numbers of their subatomic particles… isotope – an atom of the same element that has a different number of neutrons than normal “iso-” = equal / the same ex: Carbon-14 [number denotes mass, NOT charge] [typical carbon has a mass of 12] Atoms – cont’d Sometimes, however, elements can also contain different numbers of their subatomic particles… ion – a charged particle has more or less electrons than the neutral element more = negative, less = positive ex: Fe2+ [number denotes charge w/ + or - ] Practice Atomic # = 17 # of Protons? # of Electrons? Atomic Mass = 35 # of Neutrons? 18 Discuss Define the terms: Ion, Isotope How are these two terms similar? [compare] both are describing a difference in a # of a subatomic particle. How are they different? [contrast] ion = difference in electrons isotope = difference in neutrons Acids & Bases pH = parts of hydrogen concentration of hydrogen ions Acid – compound which releases hydrogen ions [H+] in water pH = 0 – < 7 stronger acids release more [H+] ions Ex: HCl [hydrochloric acid] Other facts? Acids & Bases – cont’d Base – compound which releases hydroxide [OH-] in water pH = >7 – 14 stronger bases release more [OH-] ions Ex: NaOH [sodium hydroxide] Other facts? ***NOT IN NOTES BUT NOT NEEDED: pOH – parts hydroxide - not often used, but can be calculated – we’ll never use this*** Acids & Bases – cont’d Neutral - compound that breaks apart in water and releases the same number of [H+] and [OH-] pH = exactly 7 some experiments define what a “neutral range” could be [roughly pH of 7] Acids & Bases – cont’d Equal Strength Acid + Equal Strength Base = Neutral hydrogen and hydroxide ions are equal in strength. [H+] + [OH-] HOH (hydrogen hydroxide) (water…H2O) HCl + NaOH NaCl (sodium chloride/table salt) + H2O Acids & Bases – cont’d ***ALSO NOT IN NOTES – COPY DOWN Indicator – used to identify whether a substance is an acid or a base shows this by a color change Examples: Red Cabbage water Acids & Bases – cont’d Examples – cont’d pH test strips red in acid, blue in base Discuss On the scale of 0-14, which numbers represent acids? which numbers represent bases? What kind of things help you figure out if something is an acid or a base? What color trends do you see in cabbage water and in pH strips as you move from acids to bases? Homework Take the remainder of the period and compare answers to the Acid/Base Webquest, then review your vocab. REVIEW YOUR VOCABULARY for homework there’s tons of it, so I’m not giving additional work this is the hardest unit because there’s so much vocab – so seriously, take time to learn a few words tonight!!!