Studied by 0 people
Looks like no one added any tags here yet for you.
What is chemistry the study of?
Interactions between atoms and molecules.
What is the smallest unit of matter?
An atom.
Can an atom be subdivided into smaller substances?
No, they cannot be subdivided
Atoms interact to form what?
Molecules
What are atoms composed of?
Electrons ,protons, neutrons
What are electrons?
Negatively charged particles
What are protons?
Positively charged particles
What are neutrons?
Uncharged particles.
What makes up the nucleus?
Protons and neutrons.
What moves around the nucleus?
Electrons
What are atoms with the same number of protons classified as?
The same chemical element.
What is the atomic number?
The number of protons in the nucleus
What is the atomic mass?
The total number of protons and neutrons in an atom
What are isotopes of an element?
Atoms with different numbers of neutrons.
If the atomic number of hydrogen is 1 what is the atomic mass?
1
If the atomic number of nitrogen is 7 what is the atomic mass?
14
What are the most abundant chemical elements in living organisms?
Hydrogen, Carbon ,nitrogen, and oxygen
What are electrons arranged in?
Electron shells
What do electron shells correspond to?
Different energy levels.
How do atoms form molecules?
By combining to fill their outermost shells.
What is a valence?
The number of missing or extra electrons in the outmost shell
Why do molecules hold together?
Because the valence electrons of the combining atoms form attractive forces called chemical bonds, between the atomic nuclei
Are number of protons and electrons equal in an atom?
Yes, they are equal
What are ions?
Charged atoms that have gained or lost electrons.
What are cations
Atoms that lose electrons and become positively charged ions.
What are anions?
Atoms that gain electrons and become negatively charged ions.
What are ionic bonds
Attractions between ions of opposite charge.
In an ionic bond what happens when one atom loses electrons to?
Another gains electrons.
When are covalent bonds formed?
When 2 atoms share one or more pair of electrons.
Where are covalent bonds more common and stronger?
In organisms compared to ionic bonds
When do hydrogen bonds form?
When a hydrogen atom that is covalently bonded to an O or N atom is attracted to another N or O in another molecule.
What is the molecular mass?
The sum of the atomic masses in a molecule.
What is one mole of a substance equivalent to?
Molecular mass in grams.
What is the unit of molecular mass
Dalton (da)
What do chemical reactions involve?
The making or breaking of bonds between atoms
When does a change in chemical energy occur?
During a chemical reaction
What does and endergonic reaction do?
Absorb energy
What does an exergonic reaction do?
Release energy
When does a synthesis reaction occur?
When atoms, ions or molecules combine to form new larger molecules.
What is anabolism?
The synthesis of molecules in a cell
When do decomposition reactions occur
When a molecule is split into smaller molecules, ions or atoms
What reaction is this?
Decomposition reaction.
What is an exchange reaction?
Part syntheses and part decomposition reaction
What reaction is this?
Exchange reaction
What do organic compounds always contain?
Carbon and hydrogen
How are organic compounds usually structured?
Structurally complex
What do inorganic compounds usually lack?
Carbon
How are inorganic compounds structured?
Small and structurally simple.
Is water inorganic or organic?
Inorganic
What type of molecule is water?
A polar molecule
Why is water an inorganic substance?
Because it does not have a carbon hydrogen bond.
Why is water a polar molecule?
It has an unequal distribution of charges.
Why is water a good solvent?
Water can dissolve many substances
What bonds absorb heat in water?
Hydrogen bonds
What is this?
A hydrogen bond
What are acids?
Substances that dissociate into one or more hydrogen ions and one or more negative ions
What is this?
An acid
What are bases?
Substances that dissociate into one or more hydroxide ions and one or more positive ions
What is this?
A base
What are salts?
Substances that dissociate into cations and anions neither of which is H+ or OH-
What is this?
A salt
What is the concertation of H+ in a solution expressed as
PH
What does increasing H+ increase?
Acidity
What does increasing OH- increase?
Alkalinity
What is the best ph for organisms to grow?
Between 6.5-8.5
What do organic compound commonly contain?
Hydrogen, oxygen and or nitrogen in addition to carbon
What is a carbon skeleton?
The chain of carbon atoms in an organic molecule.
What do functional groups bond to
Carbon skeletons.
What are functional groups responsible for
Most of the chemical properties of a particular organic compound.
What do the hydroxyl groups of alcohols have in common?
They have OH
What can small organic molecules combine into?
Large macromolecules.
What are macromolecules?
Polymers consisting of many small repeating molecules.
What are monomers?
Many small repeating molecules.
How do monomers join?
By dehydration synthesis or condensation reactions.
What do carbohydrates serve as?
Cell structures and cellular energy sources
What do carbohydrates include?
Sugars and starches
What elements do carbohydrates consist of?
C, H and O
What is the formula of Carbohydrates
What are isomers
Molecules with same chemical formula but different structures.
What are monosaccharides?
Simple sugars with 3-7 carbon atoms
What are examples of monosaccharides?
Glucose and deoxyribose.
How are disaccharides formed?
When 2 monosaccharides are joined in a dehydration synthesis
How can disaccharides be broken down?
By hydrolysis.
What do polysaccharides consist of?
Tens and hundreds of monosaccharides joined through dehydration synthesis
What are polymers of glucose that differ in their bonding and functions?
Starch glycogen, Dextran, cellulose and polymers
What are lipids?
Primary components of cell membrane
What do lipids consist of?
C, H and O
Are lipids soluble in water?
No, they are insoluble in water.
Are lipids nonpolar?
Yes, they are nonpolar
What are examples of simple lipids?
Fats and triglycerides?
What do simple lipids contain?
Glycerol and fatty acids.
How are glycerol and fatty acids formed?
By dehydration synthesis.
What is the structure of saturated fats
Fatty chains have no double bonds between carbon atoms , All carbon atoms are fully saturated with hydrogen atoms
What is the structure of unsaturated fats
Unsaturated fats have one or more double bonds in the fatty acid chains. These double bonds can change the shape of the fatty acids.
What is the structure of cis fats
The hydrogen atoms are on the same side of the double bond
What is the structure of Trans fats
Hydrogen atoms are on the opposite sides of the double bond
What are some complex lipids
C,H, O + P, N and or/ S
In complex lipids what are cell membranes made of
Phospholipids
What type of regions do Phospholipids have?
Polar and nonpolar regions
What makes a steroid?
4 carbon rings with and an -OH group attached to one ring
Note 
Flashcard (54)