Unit 2 Chapter 2 Chemistry

Unit 2 Chapter 2Chemistry

Matter ________________________________________.

Mass - the amount of matter an object has.___________________________. Gravity has an impact on weight.The same mass on the earth would weigh less on the moon because less gravity on moon.

Elements _____________________ cannot be broken down into simpler types of matter. Examples: oxygen, carbon, hydrogen, and nitrogen these four make up more than 90% of the mass of all living things!Periodic Table :Displays elements in an organized manner.From left to right general trend is toward larger sized atoms.See page 31 in textbook.See page 31 in textbook:Atomic Number = _____________________________.Atomic Mass = ______________________________________________________________________.Atom ______________________________that ______________________________.

Atomic Structure consists of:_________ = central core consists of ______ (+) and _________ (0). NOTE: #of protons or atomic number determines the atoms identity.2. _________ (-) orbit in energy levels or shells around the nucleus.

NOTE: # of protons = # of electrons to give an atom a net charge of zero.

3. 1st Shell (closest to nucleus) holds 2 electrons (e-)..these are the lowest energy electrons.

4. Each shell after the 1st can hold up to 8 electrons(e-)..higher energy e-s.

NOTE: In most elements, the outer shell is not filled. This determines the reactivity of the atom. See page 32 in textbook.Compound ______________________________________________. Exs.) water H0, ammonia NH, glucose CHO.

Isotopes ______________________________________________________________ it has.Ex.) C and C (radioactive and unstable)

Chemical Formula shows the kind and proportion of atoms in a compound. Ex.) H0

Chemical Reaction chemical bonds are broken, atoms rearranged, and new bonds formed.

Molecule ____________________________________________________________________of the substance and can exist in a free state.Exs.) O, O3 HO, CO, DNA, protein.See page 33 in book for bonding info:

Covalent Bonds _____________________________Ex.) HO atoms are striving for stability

Ionic Bonds:Ion = atom with a + or charge from _____________________________________.Ionic Bond occurs when ______________________________________________. Ex.) NaCl salt.

Energy _____________or cause change. Energy can change forms. Ex.) electrical can change to radiant and thermal (light bulb).

Free Energy energy available to do work.

__________________ solid, liquid, gas.depends on the motion of molecules. Ex.) Water temperature makes molecules move at different rates and turns water to solid, liquid, or gas.

Energy and chemical reactions:CO + HO HCO _________ __________

Activation Energy energy needed to start a reaction. (see graph on page 37 in textbook).

Exergonic Reactions involve a net ______________________________. Ex.) Sugar CO + water + energy.

Endergonic Reactions involve a net _____________________________. Ex.) CO + water + sunlight sugar.

Catalyst ___________________________________________________________. Ex.) ENZYMES act as catalysts. (see enzyme deficiency on page 37 in textbook.

Reduction-Oxidation Reactions (REDOX reactions):Oxidation reactant __________________and takes on a positive charge.Reduction reactant __________________ and takes on a negative charge.Ex.) Na + Cl NaCl (ionic bond)

Solution a mixture in which _________________________________________..can be liquids, solids, or gases. Ex.) Blood = iron, water, oxygen, sugar, wastesSolute a ____________________ in the solution.Solvent a _____________________________________.Concentration of Solution the amount of solute dissolved in a fixed amount of solution. Ex.) 2% saltwater = 2grams salt in 100ml water.Saturated Solution ____________________________________________________.the solution is saturated.

Aqueous Solution solutions in which ____________________________ ..very important to living things as we are made up of lots of different aqueous solutions. Exs.) blood, urine, lymph, spinal fluid, mucus.

Acids and BasesDissociation of Water force of attraction between water molecules cause them to break apart.

Pure water is neutral - # of OH and HO ions are equal.

Acid - ___________ions is greater than OH ions.

Ex.) Hydrogen chloride gas in water:

HCl H +Cl Hs make the water acid.

Bases (Alkaline) - #of _________is greater than HO ions. Ex.) Sodium Hydroxide dissolved in water: NaOH Na + OH OH ions make the water basic or alkaline.pH Scale compares the relative concentrations of OH and HO in a solution.pH change in 1 pH unit = tenfold change in acidity/alkalinity. See figure 2-10, page 42 in book. Buffers ___________________________________________________________________________________.

Complex Buffering Systems maintain pH values of your many body fluids and tissues. See figure 2-10 0n page 42 in your book.