Chapter 2-Energy And Matter Flashcards
Which particles form the nucleus of an atom?
Protons and neutrons
Positively charged particles
Protons
Negatively charged protons
Electrons
Neutrally charged particles
Neutrons
What does the atomic number represent?
The number of protons and electrons
How do you find the number of neutrons in an atom?
Subtract the atomic number from the atomic weight
What distinguishes one atom from another?
The number of protons
What gives an atom it’s certain properties?
The number of electrons
How many electrons can be held in the first energy level?
2 electrons
How many electrons can be held in the outermost layer?
8 electrons
How many electrons are held in the outermost layer in a carbon atom?
4 electrons
How many elements are found on earth?
91 elements
How many elements are found in organisms?
25 elements
A substance made of atoms of different elements bonded together in a certain ratio
Compound
An atom that has gained or lost one or more electrons to other atoms
Ion
What charge does an ion gain when it loses one or more electrons?
Positive
What charge does on ion gain when it gains one or more electrons?
Negative
Bonds formed through the electrical force between oppositely charged ions
Ionic bond
Bond formed when atoms share a pair of electrons
Covalent bond
Two or more atoms held together by covalent bonds
Molecule
Has a region with a slight positive change and a region with a slight negative charge
Polar molecule
An attraction between a slightly positive charged hydrogen atom and a slightly negatively charged atom
Hydrogen bond
What are the three properties given from hydrogen bonds?
High specific heat, cohesion, and adhesion
Property that means water resists changes in temperature?
High specific heat
The attraction among molecules of a substance, makes water molecules stick to other water molecules, creates surface tension
Cohesion
The attraction among water molecules to different molecules
Adhesion
What causes hydrogen bonds to form between polar molecules?
Polar molecules have partially charged regions that attract other polar molecules
What must happen for molecules and ions to take part in chemical processes inside cells?
They must dissolve in water
How is a solution made?
When one substance dissolves in the water in your body or other substances
A mixture of substances that is the same throughout
Solution
The substance that is present in the grater amount and the part that dissolves the other substances
Solvent
A substance that dissolves in a solvent
Solute
What is the solvent and solute in blood?
Solvent-plasma
Solute–the other dissolved substances
Why do polar molecules dissolve in water
Because the attraction between the water molecules and the solute molecules is greater than the attraction among the molecules of the solute(the pull between the water and the solute molecules is more than the solute molecules attraction keeping them together)
A compound that releases a proton when it dissolves in water
Acid
What is the difference of acids and bases?
Acids have a higher concentration of hydrogen protons
Compounds that remove hydrogen protons from a solution (have a lower concentration of hydrogen protons than acids)
Bases
Element that has four valence electrons
Carbon
What are the three structures of carbon?
Straight chains, branched chains, and rings
Each subunit in a complete molecule
Monomer
A large molecule made of many monomers branded together
Polymers
A molecule containing a very large number of atoms
Macromolecule
Polymers that have different monomers
Proteins
Polymers with one type of monomer
Starches
Molecules composed of carbon, hydrogen, and oxygen that can be broken down to provide a source of usable chemical energy for cells
Carbohydrates
Most basic carbohydrate
Sugars
Sugar made by plant cells during photosynthesis that have 6 carbon atoms
Glucose
Any of a class of sugars who’s molecules contain two monosaccharide residues
Disaccharide
Another term for sugar
Saccharide
Polymers of monosaccharides
Polysaccharides
What type of bonds link monomers in proteins?
Peptide bonds
What is the relationship between starches and cellulose?
Starches and cellulose are the polymers of glucose
Carbo that has a straight rigid structure and makes up the cell wall in plant cells
Cellulose
No polar molecules that include fats, oils, and cholesterol
Lipids
Chains of carbon atoms bonded to hydrogen atoms
Fatty acids
What is the major difference between saturated and unsaturated fats?
Saturated fats only have carbon-carbon single bonds and unsaturated have double bonds
What do the double bonds in unsaturated fats result in?
The fat being a liquid/oil
Three fatty acids bonded to glycerol
Triglycerides
Consists of glycerol, two fatty acids and a phosphate group
Phospholipid
Lipid that the body needs for steroid her ones
Cholesterol
A polymer made of amino acids
Protein
Molecules that contain carbon, hydrogen, oxygen, nitrogen, hydrogen, and sometimes sulfur
Amino acid
What is every amino acid bonded to?
A hydrogen atom, an amino acid, and a carboxyl group,
Polymers that are made of monomers called nucleotides
Nucleic acids
What are the two types of nucleic acids?
DNA and RNA
Nucleic acid that gives the instructions to build proteins
DNA
Nucleic acid that actually builds the proteins
RNA
Change substances into different substances by breaking and forming chemical bonds
Chemical reactions
The substances changed during a chemical reaction
Reactants
The substances made by a chemical reaction
Products
How are bonds broken and formed?
Energy is added to break bonds
The amount of energy that will break a bond
Bond energy
When both the reactant and products are being made at the same rate
Chemical equilibrium
The amount of energy that needs to be absorbed for a chemical reaction to start
Activation energy
Chemical reactions that release more energy than they absorb
Exothermic reactions
If more energy is absorbed than released in a chemical reaction
Endothermic reactions
A substance that decreases the activation energy needed and increase the rate of the reaction
Catalyst
Catalysts for chemical reactions in living things
Enzymes
What factors can affect an enzymes shape and function?
Temperature and pH
Specific reactants that an enzyme acts on
Substrates
What happens to the substrates once they are in the active sites that causes them to chemically react easier?
They become strained and become chemically weaker