CCU bio ch2

matter

refers to anything that takes up space and has mass

solid, liquid, gas

in what states can matter exist?

elements

what is mass composed of?

element

substance that cannot be broken down into another substance by ordinary chemical means

92

how many naturally occurring elements are there?

4; 96%; carbon, hydrogen, oxygen, nitrogen

__(how many)__ elements make up about ___% of the body weight of most living organisms -- ____, ____, ____, and ____

atomic theory

what states that elements consist of atoms?

atomic symbol

name of the atom or element

H

what is the atomic symbol for hydrogen?

Na

what is the atomic symbol of sodium?

neutrons, protons, electrons

what are the subatomic elements?

neutrons

subatomic elements with no electrical charge, found in the nucleus

protons

subatomic elements with positive charge, found in the nucleus

electrons

subatomic elements with negative charge, found outside of nucleus moving in orbitals

sum of protons and neutrons

what is mass number equal to?

about zero

how much mass do electrons have?

with gravity

how does atomic weight change?

atomic number

all atoms of an element have this same number of protons; gives number of electrons if an atom is electrically neutral

isotopes

atoms of the same elements that differ in the number of neutrons

protons

what do isotopes have the same number of?

neutrons

what do isotopes have a different number of?

mass numbers

the number of protons and neutrons

true

true/false: isotopes are unstable and may decay

radiation

what do isotopes emit when they decay

true

true/false: radioactive isotope behavior is essentially the same as a stable isotope of same elements

1) as tracer -- PET scan

2) to sterilize medical equipment

how can radioactive isotopes be used?

cancer

what does damage to cells caused by radioactive isotopes lead to?

periodic table

table in which elements' chemical and physical characteristic recur in a predictable manner

in periods and groups

how are atoms arranged in periodic tables?

rows

what are periods in a periodic table?

columns

what are groups in a periodic table?

true

true/false: electrons are constantly moving

atoms with energy levels or electron shells

what kind of models are moving electrons useful for constructing?

2

how many electrons fill the first shell of atoms up through number 20?

8

how many electrons fill the additional shells of atoms up through number 20?

valence shell

the outermost shell

2; outer; 8

according to the octet rule of valence shell: if an atom has more than ____ shells, the ____ shell is most stable with ___ electrons

give up, accept, share electrons

according to the octet rule of valence shell: what can atoms do to have eight electrons?

the arrangement of their electrons

what are chemical properties of atoms largely determined by?

molecule, compound

what are the types of chemical bonds?

molecule

a group of atoms bonded together

O2, H2O, C6H12O6, N2

examples of molecules

compound

a molecule containing atoms of more than one element

H2O, C6H12O6

examples of compounds

ionic, covalent

what are the two types of bonds?

ionic bond

what kind of bond forms when two atoms are held together by the attraction between opposite charges?

a metal and a non-metal

which elements does an ionic bond usually happen between?

sodium

which element has 1 electron in valence shell?

gives up

sodium usually (gives up/accepts) an electron during ionic bonding

chlorine

which element has 7 electrons in valence shell?

accepts

chlorine usually (give ups/accepts) an electron during ionic bonding

ions

what are charged atoms?

sodium

after ionic bonding, which element (sodium/chlorine) has more proton than electrons?

chlorine

after ionic bonding, which element (sodium/chlorine) has more electron than protons?

ionic compound

the result of ionic bonding

salt

which ionic compound is formed by ionic bonding of chlorine and sodium?

covalent bond

what kind of bond forms when two atoms share electrons to complete the outer shell?

two non-metals

which elements does a covalent bond usually happen between?

orbitals

what overlaps when two atoms share electrons to fill their outer shell?

structural formula

which formula uses straight lines H-H?

one pair of shared electrons

in a structural formula, what does one line indicate?

molecular formula

which formula simply shows number of atoms involving H2?

cation

what is a positively charged ion?

anion

what is a negatively charged ion?

double covalent bond

what type of bond occurs when two atoms share four electrons?

true

true/false: double bonds are stronger than single bonds

chemical formula

which formula represents the types and numbers of atoms in molecules?

H₂O: two hydrogen atoms and one oxygen atom in a water molecule

give an example of a chemical formula

reactants

what are molecules that participate in reactions?

to the left of the arrow

on which side of the arrow are the reactants shown in a chemical equation?

products

molecules formed by reactions

to the right of the arrow

on which side of the arrow are the products shown in a chemical equation?

equation; same; each; both

an ____ is balanced if the ____ number of ____ type of atom occurs on ____ sides of the arrow

photosynthesis; 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂

an example of a balanced chemical equation is the _____ equation: state the equation

C₆H₁₂O₆

what is the molecular formula for glucose?

water

what is the single most important molecule on Earth?

70-90%

all organisms are ___-___% water

true

true/false: water has unique properties that make it a life-supporting substance

structure; molecule

properties stem from the ____ of the ____

polar covalent bond

what type of bond does water have?

electrons

in the structure of water: which of the following do atoms not share equally?:(neutrons/protons/electrons)

electronegative; hydrogen

in the structure of water: oxygen is more ____ than ____

oxygen; hydrogen

in the structure of water: electrons spend more time around the ____ nucleus than the ____ nuclei

oxygen; hydrogens

in the structure of water: ____ end becomes slightly negative; ____ become slightly positive

no

in the structure of water: is it considered an ionic bond or ions when the oxygen end becomes slightly negative/ hydrogens become slightly positive?

hydrogen bond

what type of bond is it?: slightly positive hydrogen of one water molecule attracted to the slightly negative oxygen in another water molecule

- solvency

- cohesion and adhesion

- high surface tension

- high heat capacity

- high heat of vaporization

- varying density

give a list of the overview of the properties of water (KNOW ALL)

true

true/false: water is a solvent

polarity; H-bonding

solvency of water: due to ____ and ____, water dissolves many substances

hydrophilic

molecules that are attracted to water

hydrophobic

molecules that are not attracted to water

NaCl

solvency of water: water causes ____ to dissociate

solution

what is a uniform mixture?

dissolving

the process by which one substance is broken up into smaller pieces, usually ions by another substance

water; salt crystal

example of dissolving: ____ molecules tear apart the _______ until it is completely dissolved in the solution

solvent

in the process of water dissolving a salt crystal: is water the solvent or the solute?

solute

in the process of water dissolving a salt crystal: is the salt crystal the solvent or the solute?

concentration

the amount of solute that is packed into a solvent

acid; hydrogen

an ____ is a substance that dissolves in water to form ____ ions

H⁺

what is the chemical symbol for a hydrogen ion?