bio exam 2

Atom

smallest unit of matter that

contains the properties of an element

Proton +1, Neutron, Electron -1

Atoms are made up of what 3 characteristic

(subatomic particles)

nucleus

Atoms are arranged with the protons

and neutrons held in the center of the?

electron shells or a cloud

what do electrons form around the outside?

uncharged

In what atom (NOT an ion) does the

number of protons = electrons

zero, two -1 electrons

total charge = what two +1 protons = what

electron shells

electrons exist in rings outside the nucleus called

inside to out

do electrons fill shells inside to out or out to inside

Ionic bond

an electron is fully donated from one atom and accepted by

another

ions (charged atoms)

what do ionic bonds generate

Covalent bond

formed when each atom shares its electrons. Electrons

are NOT transferred and so fully charged ions are NOT created.

Each atom “feels” like it has a full outer ring.

Molecule

joining of 2 or more atoms by a covalent bond

covalent

in what bond are the atoms only “happy” as

long as it continues to share in the bond.

Single covalent bond

only a single pair of

electrons is shared (2 electrons total); H2

Double covalent bond

sharing of two pairs of

electrons (4 electrons total); O 2

Triple covalent bond

sharing of three pairs of

electrons (6 electrons total); N2

Quadruple covalent bond

sharing of four pairs

of electrons (8 electrons total); rarely seen

triple > double > single

bond strength order?

Carbon

what element needs to form four total covalent bonds to fill its outer ring.

Nonpolar covalent

Equal sharing

when electrons stay in the middle;

neither feels slightly positive or

slightly negative

Polar covalent:

an electron “hog”

pulls the electrons closer to it making

itself slightly negative and whatever it

is pulling from slightly positive.

Polar covalent bonds

what bonds create partial

charges

Hydrogen bonds

interactions between slightly positive

hydrogen and a slightly negative oxygen or nitrogen

Capillary action (cohesion), Surface tension, Ice floats (lower density), Absorbs heat, Solvent properties

Water hydrogen bonding gives rise to

several of its properties:

Hydrophobic

water-fearing

Hydrophilic

water-loving

C. 19 protons, 20 neutrons

The atomic number of potassium is 19. The mass number of

potassium is 39. How many protons and neutrons does

potassium have?

A. 19

The atomic number of potassium is 19. The mass number of

potassium is 39. How many electrons does a potassium

atom have?

A. True

In a single covalent bond, two atoms share a

pair of electrons

D. both polar and nonpolar covalent bonds

This is the molecule glucose. It has…

A. +

The oxygen atoms in water interact with _____ ions.