Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
33 Cards in this Set
- Front
- Back
|
What is an isotope? |
Elemental atoms that differ in mass due to different number of neutrons |
|
|
What is the Law of Definite Proportions? |
For a given compound, the elements always combine in the same proportion. |
|
|
Law of Multiple Proportions |
Two elements can form different compounds by combining in different proportions (which can be represented as a small, whole number ratio) |
|
|
Thomson's charge-to-mass experiment |
Investigated the effect on a cathode ray of placing an electric field around a tube. Found that 1) Charged matter is attracted to an electric field and 2) Light's path is not deflected by an electric field. Cathode ray particles became known as electrons. |
|
|
Millikan oil drop experiment |
Investigation led to determining charge of the electron. |
|
|
What is the charge of an electron? |
-1.60 x 10^19 C |
|
|
What is the mass of an electron? |
9.1 x 10-28 g |
|
|
What is the J.J. Thomson plum-pudding model? |
An atom is composed of a positive cloud of matter in which electrons are embedded (explains the positive, negative charged behavior) |
|
|
Rutherford's Gold Foil Experiement |
Could not explain plum pudding atom model, lead to discovery of atom's nucleus. [1) Nucleus is tiny, dense center of atom. 2) Nucleus has essentially the entire mass of the atom, because electrons add practically no mass. 3) The nucleus is positively charged. |
|
|
What is the mass (in g) of a proton? |
1.67262 x 10^-24 |
|
|
What is the mass (amu) of a proton? |
1.00727 |
|
|
What is the symbol for a proton? |
p, p+, H+ |
|
|
Where is a proton located? |
nucleus |
|
|
Where is an electron located? |
Empty space |
|
|
What is the charge of an electron? |
-1 |
|
|
What is the symbol of an electron? |
e, e- |
|
|
What is the mass of a neutron (in g)? |
1.67493 x 10-24 |
|
|
What is the mass amu of a neutron? |
1.00866 |
|
|
Where is a neutron? |
Nucleus |
|
|
What is the charge of a neutron? |
0 |
|
|
What is the symbol for a neutron? |
n, n0 |
|
|
What determines an element's identity? |
Number of protons |
|
|
What determines an atomic number? |
Number of protons |
|
|
What makes up a mass number? |
protons + neutrons |
|
|
What is atomic weight? |
Weighted average of weights of naturally occurring atoms |
|
|
Ions |
Atoms/groups of atoms with a positive or negative charge |
|
|
What happens when you take away an electron? |
Cation with a positive charge (more protons in nucleus than electrons surrounding). Metal elements tend to form cations. |
|
|
What happens when you add an electron? |
Anion with a negative charge (fewer protons in nucleus than electrons surrounding). Nonmetals tend to form anions. |
|
|
Periodic law |
When elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically. |
|
|
Metals |
1) solid at room temp (exception: Hg) 2) conduct heat and electrical current 3) malleable 4) Lose electrons to form cations |
|
|
Nonmentals |
1) found in all three states 2) poor conductors 3) solids are brittle 4) gain electrons to become anions 5) found mostly in upper right of periodic table (except h) |
|
|
6.02 x 10^23 units |
Avogadro's number / 1 mole |
|
|
Mole and mass relationship |
An element's molar mass in grams/mole is numerically equal to the element's atomic mass in atomic mass units. (Example: 12.01 g carbon = 1 mol carbon = 6.022 x 10^23 C atoms) |
