Chemistry-chpt 2 Flashcards
Element
Pure substance= building block of matter
Matter
Substance that takes up space
How many naturally occurring atoms elements are there?
92
Moat important elements to living things?
Carbon Hydrogen Nitrogen Oxygen Phosphorus Sulfur
CHNOPS
Atom
Smallest unit of an element
Which has more energy
- Inner shell
- Outer shell
Outer
Atomic number
Number of protons
Atomic mass
Proton and neutrons together
Periodic table
- first letter of element is used as symbol
- atomic number places above atomic symbol
- arranged horizontally by increasing atomic number
- arranged vertically by number of electrons in outer most shell
Isotopes
atoms of the same element that have the same atomic number but different numbers of neutrons
What does atomic mass represent
Average atoms of each element
What do unstable isotopes do as they decay
Emit radioactive particles
Uses for radioactive isotopes
Carbon dating
Radioactive tracers in medical tests
Medical imaging
Radioactive therapy
Molecule
Formed by the bonding of two atoms combined
Compound molecule
Molecule composed of atoms of two or more different elements
Ionic bond
Electrostatic interaction between cation and anion
Why do atoms react with other atoms
To get a full outer electron she’ll
Ion
An atom which has lost if gained electrons bc of a chemical reaction
Covalent bond
Bond that holds Atoms together to form molecules
Are electrons shared or transferred in covenant bonds ?
Shared
Are atoms shared or transferred in ions and ionic bonds?
Transferred
Acids
Molecules that release hydrogen ions(atoms that lost an electron) when dissolved in water
Bases
Extra electrons
pH scale
Measure the positive and negative charges of atoms
Nonpolar covalent bond
Electrons shared equally
Polar covalent bond
Electrons shared unequally ( normally happens of atoms are different from one another)
Electron dot formula
Shows only outermost electrons
Molecular formula
Only the number of each type of atom in a molecule is represented
Structural formula
Lines represent shared electrons
Molecules are 4-d 3-d or 2-d
3-d
What do molecular shapes determine
Function
How much does water make up in living things
70%
Which ends are positive and negative in a water molecule
Oxygen- negative
Hydrogen-positive
Polar molecules
Have a positive and negative end
Hydrogen bond
Attraction between positive end in one molecule and negative in another molecule
Properties of water due to hydrogen bonding and polarity
- universal solvent
- liquid at room temperature and body temperature
- water molecules are cohesive(one molecule sticks to another)
- high specific heat-resist change in temperature
- high heat of vaporization - keeps body from overheating
- water is less dense at 4°C so ice floats on liquid water
What equal parts does water break into
Hydrogen ions(H+) and hydroxyl ions(OH-)
What does acid release
H+
What does bases release
OH-
Acidic solution
- have sour taste
- release hydrogen ions when they break up in water
- ex:coffe lemon juice and vinegar
Basic solutions
- have bitter taste
- feel slimy or slippery to touch
- release hydroxyl ions
- ex: ammonia and sodium hydroxide
Buffer
Substance that resists change in pH
Buffed consists of
Chemical or group of chemicals
Buffers function by
Binding excess hydrogen ion or hydroxyl ions
What do ALL organic molecules contain
Hydrogen and Carbon
Large macromolecule
Polymers
Monomers
Small organic molecules
Organic molecules are composed of smaller units called monomers.
-further explain monomers?
- monomers are small organic molecules
- either exist separately or are bonded together to form polymers
Dehydration synthesis
- links monomers together to form a polymer
- 2 hydrogen and 1 oxygen removed in reaction and unite to form water
- water is always a biproduct
Hydrolysis
- Polymer is broken down to monomers
- water is required to replace 2 hydrogens And the oxygen
Glycoproteins
Sugar protein that is unique to every individual, every cell in your body has this glycoprotein. If a cell doesn’t have it than it is destroyed by your immune system
Carbohydrates
- ration of Hydrogen atoms to Oxygen atoms is 2:1
- “hydrates of carbon”
- atomic grouping of H-C-OH
Function of carbohydrates
- principal energy source
- short term energy storage
- structural components
- cell to cell recognition=surface antigens
Glucose molecular formula
C6 H12 O6
Saccharide
Sugar ring
Simple carbohydrates
Monosaccharides (1)
Disaccharides (2)
Monosaccharides
Simple sugars like glucose and fructose
Disaccharides
2 monosaccharide bonded together
Examples of Disaccharides
Sucrose (glucose+fructose)
Galactose (glucose+lactose)
Maltose( glucose+glucose)
Polysaccharides
Large polymers of monosaccharides
Cellulose
- structural carb in plant
- “fiber”
- indigestible by human enzymes
Starches and Glycogen
- quick energy storage
- starches are long chains of
Sucrose
Glucose
Fructose
Galactose
Glucose
Lactose
Maltose
Glucose
Glucose