unit 1 - chapter 2 (chemical context of life)

Question 1

what is matter conceptually?

Answer 1

substance, takes up spaces, has mass, can exist as solid/liquid/gas, comprised of elements

Question 2

what is matter chemically?

Answer 2

consists of chemical elements in pure form and in combinations called compounds

Question 3

what is an element?

Answer 3

substance which cannot be broken down by chemical means

Question 4

what is a compound?

Answer 4

substance of 2 or more elements in a fixed ratio

Question 5

what is an atom?

Answer 5

“uncuttable” thing

Question 6

what is a nucleus?

Answer 6

central part of atom

Question 7

what is a proton?

Answer 7

positive charge nuclear particle

Question 8

what is an electron?

Answer 8

negative charge atomic particle

Question 9

what is a neutron?

Answer 9

no charge nuclear particle

Question 10

what is an amu also equivalent to?

Answer 10

a dalton

Question 11

how much smaller is an electron than a proton or neutron?

Answer 11

electron is 1/2000 the mass of a proton or neutron

Question 12

what is an isotope?

Answer 12

same element, same # of protons, different # of neutrons, different mass

Question 13

what happens to unstable isotopes?

Answer 13

they will decay or lose particles and release energy and eventually cause radiation

Question 14

what is radioactivity measured with?

Answer 14

a Geiger center

Question 15

what is radioactivity used for?

Answer 15

used as tracers and used to date

Question 16

is the nuclei directly involved in chemical processes?

Answer 16

no

Question 17

what is energy?

Answer 17

the capacity to do work or effect change, it comes in many forms

Question 18

what is potential energy?

Answer 18

energy of position or structure

Question 19

how are molecules formed?

Answer 19

through chemical bonds

Question 20

how do strong chemical bonds form?

Answer 20

they form bc atoms are more stable when their valence shells are filled

Question 21

what are the 2 stronger bonds?

Answer 21

intramolecular bonds; covalent and ionic

Question 22

what are the 2 weaker bonds?

Answer 22

intermolecular bonds; hydrogen bonds and Van der Waals interactions

Question 23

what is a covalent bond?

Answer 23

2 atoms share a pair of electrons and this completes both of their valence shells

Question 24

what is a polar covalent bond?

Answer 24

the uneven sharing of electrons

Question 25

what is an ionic bond?

Answer 25

1 atom "gives" valence electron to another atom to complete valence shell

Question 26

what is an ion?

Answer 26

charged atoms or molecules where the number of protons doesn't equal the number of electrons

Question 27

what is a positively charged ion called?

Answer 27

cation

Question 28

what is a cation?

Answer 28

a positively charged ion

Question 29

what is a negatively charged ion called?

Answer 29

anion

Question 30

what is an anion?

Answer 30

a negatively charged ion

Question 31

what affects ion bond strength?

Answer 31

environment

Question 32

what do bonds contribute to molecules?

Answer 32

the shape, shape is essential to function

Question 33

what do chemical reactions do to bonds?

Answer 33

they make or break them

Question 34

in what types of molecules does van der waals attraction happen?

Answer 34

non-polar molecules

Question 35

what is weaker, van der waals attraction or hydrogen bonds?

Answer 35

van der waals attraction

Question 36

what is van der waals attraction?

Answer 36

asymmetry in charge distribution