What are the main parts of an atom? Essential Question
Matter: All living things are made of matter. Matter is anything that has mass and takes up space. Properties –physical property description of shape, mass, volume melting point, boiling point –chemical property structure of molecules which make up substance how substance reacts with another
Matter Elements –element a substance that can not be broken down into a simpler substance –25/90 elements are essential to life CHNOPS – 6 greatest You must know the symbols
Matter atom –smallest particle of an element that has the characteristics of that element Biochemistry
Atoms atom structure –nucleus center, contains neutrons & protons –neutrons –carries no charge, neutral = n 0 –protons carries a positive charge = p +
Atoms atom structure –electron electrons carry a negative charge = e -
Atoms atom structure –electron electrons orbit nucleus in separate energy levels or clouds –1 st shell= 2 electrons –2 nd shell= 8 electrons –3 rd shell= 18 electrons –4 th shell= 32 Keep in mind that not each shell must be full before moving to the next level Biochemistry
Atoms periodic table 2 He Helium 4.002602 The atomic number tells us the # of protons. It is unique to each atom. How do we determine the number of electrons? The mass number tells us the # of protons + neutrons. How do we determine the number of neutrons?
Isotopes Isotopes are atoms of the same element that have different numbers of neutrons.
Compounds Compounds are substances composed of atoms of 2 or more different elements that are chemically combined Uses molecular formula to designate –NaCl –H 2 O (the properties of a compound are different from those of its individual elements)
How are covalent and ionic bonds different? Essential Question
covalent bond –atoms share electrons ex: water, sugars, proteins ionic bond –Electrons are transferred between atoms »An atom that has gained or lost an electron (therefore, has a charge) is known as an ion.
chemical bonds covalent bond ionic bond Biochemistry
Chemical Reactions Chemical Reactions occur when bonds between atoms are formed or broken, causing substances to combine and recombine as different molecules. All of the chemical reactions that occur within an organism are referred to as that organism’s metabolism. »H 2 0 means 2 Hydrogen atoms for every 1 Oxygen atom. 5H 2 0 means 5 molecules of water. How many atoms are in 5H 2 0?
What ions are released by an acid and a base in water? Essential Question
Mixtures and solutions mixture –combination of substances in which individuals retain individual properties ex: mixed sugar and sand, oil and water solution –mixture of one or more solutes are evenly distributed in a solvent ex: salt in water
Mixtures and solutions solution –solute substance which dissolvesex: sugar –solvent holds dissolved substanceex: water –the greater the solute = greater the concentration
Acids and bases pH –measure of how acidic or basic a solution is acid –forms hydrogen ions (H+) in water –pH below 7 base –forms hydroxide ions (OH-) in water –pH above 7 pH scale ranges from 0 to 14 with acids below 7 and bases above 7.
How to Test for pH 1. Litmus Paper: only if an acid or base –Red and Blue paper –Red changes to Blue = Basic –Blue changes to Red = Acid 2. pH paper –Gives you an exact pH # by color change 3. Digital pH Meter –Gives a digital readout
Essential Question What are the properties of Water?
Water polar molecule –molecule with uneven distribution of charge –water is polar, O atom pulls e-’s from H atoms
Water hydrogen bond –weak attraction between hydrogen and oxygen atoms in different molecules
Water properties of water –water resists temperature change –water expands when it freezes –cohesion water molecules attracted to each other –adhesion water molecules attracted to sides of container Biochemistry
Water properties of water –water resists temperature change Biochemistry
Water properties of water –water expands when it freezes Biochemistry
Water –cohesion Water molecules attracted to each other Biochemistry
Water –adhesion Water molecules attracted to sides of container Biochemistry
Water & Diffusion Diffusion »Brownian motion is the random, erratic movement of particles. »Diffusion is the net movement of particles from an area of higher concentration to an area of lower.Diffusion »What is the result of diffusion?
Essential Question What are the major life substances (compounds) and what purpose do they serve?
–isomer compounds with same number elements but different structure
–monomer Small molecule that can be bound to other monomers to form polymers –polymer larger molecule formed from smaller subunits Condensation forms polymers Hydrolysis breaks down polymers
Life Substances Substances that make up living things are known as organic compounds. Organic compounds always contain C and H, but often contain other elements such as O, N, P, S.Organic compounds Macromolecules