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1
Q

definition of element

A

fundamental substance that can’t be chemically changed or broken down

2
Q

how many elements are there?

A

118

3
Q

what is the most abundant element in the human body and on the earth’s crust

A

oxygen

4
Q

periodic table definition

A

organized chart of elements with their names, symbols, and other info

5
Q

who arranged the elements in a table to show that there were more elements to be found

A

Dmitri Mendeleev

6
Q

what are periods

A

organized 7 horizontal rows

7
Q

what are groups in the periodic table

A

18 vertical colomns

8
Q

how are the elements arranged in the periodic table

A

they are grouped by similar chemical properties

9
Q

property definition

A

any characteristic to describe or identify matter

10
Q

what are examples of properties

A

volume, amount, odor, color, temp

11
Q

what is an intensive property

A

temp and melting point don’t depend on amount of the sample

12
Q

what is an extensive property

A

(length and volume) depend on amount and sample size

13
Q

what is a physical property

A

Any property you can see, smell, touch, hear or otherwise detect and measure without performing a chemical reaction

14
Q

chemical property

A

characteristics involve a change in chemical makeup

15
Q

what are the elements in group 1A named?

A

alkali metals

16
Q

what are the elements in group 2A named?

A

alkaline earth metals

17
Q

what are the elements in group 7A named?

A

halogens

18
Q

what are the elements in group 8A named?

A

Noble gases

19
Q

where are the nonmetals location

A

mostly on the right side of the table, besides helium

20
Q

what elements are best conductors of electricity

A

metals

21
Q

noble gas porperties

A

colorless gas
low reactivity
helium and neon don’t combine w/ any other element

22
Q

halogen properties

A

only found in nature w/ another element

colorful, cohesive metals

23
Q

alkaline earth metal properties

A

silvery metals

less reactive than 1A

24
Q

alkali properties

A

high reactivity
react with water rapidly
(hydrogen is in group one, but isn’t a alkali)

25
Q

What is the largest category of elements

A

metals

26
Q

How many semi metals are there? and where are they located?

A

7 elements and they are diagonal on the right side between the metals and nonmetals

27
Q

what are chemical compounds

A

atoms of different elements joining together in different ways to yield a vast number of different substances

28
Q

what is a chemical formula

A

lists the symbols of it’s constitutes and uses subscripts to indicate number of atoms EX: NaCl

29
Q

what is a chemical equation

A

reactant substances undergoing changes written out to see the change EX: 2HgO –> 2Hg + O2

30
Q

law of mass conservation definiton

A

mass is neither created nor destroyed in chemical reactants

31
Q

law of definite proportions definiton

A

different samples of a pure chemical compound always contains the same proportions of the elements by mass

32
Q

law of multiple proportions definiton

A

elements can combine in different ways to form different chemical compounds, whose mass ratios are simple WHOLE NUMBER multiplier of each other

33
Q

what is Dalton’s theory

A

elements are made up of atoms
same mass of elements = same element
atoms never change, just their ratios

34
Q

what are atoms

A

tiny particles that make up elements

35
Q

what is Thompson’s experiment

A

Cathode-ray tube–
high voltage electric currents going from a negative electrode, to a positive electrode. Proposed electrons were in the metals

36
Q

3 things that affect magnetic deflection

A

strength of deflecting magnet
size of negative charge on electron
mass of electron

37
Q

what is an ionic bond

A

share electrons by transferring 1+ of them

38
Q

what are ions

A

charged particles

39
Q

what are cations

A

positive ions, (by losing electrons)

40
Q

what are anions

A

(by gaining electrons)

41
Q

Are cations typically metals or nonmetals?

A

Metals

42
Q

are anions typically metals or nonmetals?

A

nonmetals

43
Q

what is an ionic solid

A

equal numbers of ions packed together with opposite attractions EX: Na+ & Cl-

44
Q

what are polyatomic ions?

A

charged covalent groups of atoms

45
Q

what are binary ionic compounds

A

2+ elements in a ionic compound

46
Q

When writing a binary ionic compound, how do you write it?

A

positive ion 1st
negative ion 2nd
add “ide” at the end

47
Q

what two categories fall under pure substances

A

elements and chemical compounds

48
Q

what experiment did Millikan conduct

A

mist voltage experiment and found electron mass

49
Q

What was Rutherford’s experiment?

A

found nucleus in atoms by shooting alpha particles through foil & and having some of them reflect

50
Q

nucleus defintion

A

tiny central core in atom

51
Q

what is the nucleus composed of?

A

Protons and electrons. elements differ in size of nucleus based on how many they have

52
Q

proton defintion

A

positively charged; opposite charge of electron

53
Q

neutron defintion

A

no charge, equal mass to protons

54
Q

atomic number defintion

A

number of protons IN the nucleus and number of neutrons AROUND the nucleus
EX: helium= atomic number 2= 2 protons

55
Q

mass number defintion

A

number of protons and neutrons in an atom

56
Q

isotope defintion

A

identical atomic number but diff. mass and diff. amounts of neutrons

57
Q

atomic mass defintion

A

specific atom’s mass; numerically close to mass number

58
Q

atomic weight defintion

A

average of natural isotope masses of an element

59
Q

how do you mathematically find atomic weight of an element?

A

(element 1 mass)(abundance) + (element 2 mass)(abundance)

60
Q

what is a mole

A

SI unit for amount

61
Q

what is molar mass

A

amount of mass of an element in grams to moles

62
Q

mixture

A

blend of 2+ substances w/o chemical change

63
Q

chemical compound

A

atoms of different elements combining into a new substance

64
Q

chemical bonds

A

electrons forming connections to join atoms together into compounds

65
Q

covalent bonds

A

2 atoms sharing 2+ electrons

66
Q

what is the most common bond type?

A

covalent bonds

67
Q

what is a molecule

A

result of 2+ atoms joined together by covalent bonds

68
Q

what do ball-stick models show?

A

atoms connected together by covalent bonds

69
Q

what do space filling models show?

A

show molecular shape but not bonds

70
Q

structural formula

A

shows specific connections

71
Q

diatomic molecules

A

molecules whose same atoms are held together by covalent bonds

72
Q

what are diatomic elements

A
H2
N2
O2
F2
Cl2
Br2
I2