Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Chapter 3 > Flashcards

Chapter 3 Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Who first defined an atom? How?

A

Democritus; he defined the atom as the smallest indivisible particle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

chemical reaction

A

transformation of a substance or substances into one or more new substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

examples of chemical reactions

A

burning, rusting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

law of conservation of mass

A

matter cannot be created nor destroyed during ordinary chemical reactions or physical changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

law of definite proportions

A

a chemical compound always contains the same elements in exactly the same proportions by mass regardless of size of the sample or source of the compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

law of multiple proportions

A

if two or more different compounds are composed of the same two elements, then the ratio of masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the five postulates of Dalton’s Atomic Theory?

A
  1. all matter is composed of extremely small particles called atoms
  2. atoms cannot be created, destroyed, or subdivided
  3. atoms of a given element are identical in size, mass, and other properties
  4. atoms of different elements combine in simple, whole number ratios to form chemical compounds
  5. in chemical reactions, atoms can be combined, separated, or rearranged
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which two of Dalton’s postulates are incorrect?

A
  1. atoms can actually be subdivided into smaller particles known as protons, neutrons, and electrons
  2. atoms of a given element are not always identical in mass due to varying number of neutrons in isotopes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

atom

A

smallest particle of an element that retains its chemical properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

nucleus

A

very small region located at the center of the atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the nucleus made up of?

A

subatomic particles known as protons and neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the nucleus’ charge?

A

positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What surrounds the nucleus?

A

electron cloud made up of negatively charged particles called electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Electrical charge, mass number, and location of subatomic particles?

A
  1. proton- electrical charge is positive, mass number is one, and location is inside the nucleus
  2. neutron- no charge, mass number is one, and location is inside nucleus
  3. electron- negative charge, mass number is zero, and location is outside of nucleus in electron cloud
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Who are the three main people that used experiments to discover important parts about the atom?

A

Rutherford, Robert A. Millikan, and JJ Thompson

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What was JJ Thompson’s experiment, and what did he discover?

A

JJ Thompson used a cathode ray tube to measure the charge to mass ratio of an electron; he deflected the negatively charged particles of the cathode ray with a magnet because opposite charges attract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What was Robert A. Millikan’s experiment, and what did he discover?

A

Millikan used the oil drop experiment to measure the charge of an electron. He set up a tube where electrons would latch onto oil droplets and fall through a hole into an electrically charged area where negatively charged particles would float against gravity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How were scientists able to find the mass of an electron?

A

Using the information found from Thompson’s and Millikan’s experiments, the mass and charge of an electron could be determined.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What was Rutherford’s experiment, and what did he discover?

A

Rutherford did the gold foil experiment and discovered the nucleus. He shot positive particles through an atom, and these particles deflected off of the nucleus because similar particles repel.

20
Q

How was Rutherford able to determine the size of the nucleus?

A

Since positive particles reflected off of the nucleus, he could look at the area where particles were not deflected and infer the size of the nucleus.

21
Q

What is an atom’s charge?

A

electrically neutral because the positive charge is equal to the negative charge

22
Q

How do nuclei of different elements differ?

A

they only differ in their number of protons and the amount of positive charge they possess

23
Q

What determines an atom’s identity?

A

number of protons

24
Q

What is a strong nuclear force?

A

an attraction between two subatomic/ nuclear particles, such as proton-neutron, proton-proton, neutron-neutron, etc.

25
Q

size of atoms

A

radius of an atom is the distance from the center of the nucleus to the outer portion of the electron cloud

26
Q

What is the unit of measurement for an atom?

A

picometer

27
Q

What is the atomic number?

A

the number of protons in each atom of an element

28
Q

How many protons do different atoms of the same element have?

A

all atoms of the same element contain the same amount of protons

29
Q

What are isotopes?

A

atoms of the same element that have different masses

30
Q

Compare and contrast isotopes.

A

all isotopes have the same number of protons and electrons and a different number of neutrons

31
Q

What to most elements consist of?

A

mixtures of isotopes

32
Q

What is the mass number?

A

total number of protons and neutrons in the nucleus

33
Q

What is hyphen notation?

A

the name of the element, a hyphen, and then the mass number

34
Q

example of hyphen notation

A

Carbon-12

35
Q

What is a nuclide?

A

general term for a specific isotope of an element

36
Q

What is standard relative mass?

A

comparing units of atomic mass, or amu, to the atomic mass of a Carbon-12 atom

37
Q

What is the standard relative mass of Carbon-12?

A

12 amu

38
Q

What is one atomic mass unit equal to?

A

one amu is equal to 1/12 the mass of a Carbon-12 atom

39
Q

What is the average atomic mass?

A

the weighted average of atomic masses of naturally occurring isotopes of an element

40
Q

How is average atomic mass found?

A

multiplying the atomic mass of each isotope with its relative abundance in decimal form and adding the results

41
Q

What is a mole?

A

amount of substance that contains as many particles as there are atoms in exactly 12g of Carbon-12

42
Q

What is Avagadro’s number?

A

6.022 x 10^23

43
Q

What does Avagadro’s number represent?

A

number of particles in exactly one mole of a pure substance

44
Q

What is molar mass?

A

mass of one mole of a pure substance

45
Q

What is the unit for molar mass?

A

g/mol

46
Q

What is molar mass equal to?

A

numerically equal to atomic mass of an element in amu

Chemistry (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions