Chapter 2 from Chem 1303 – Flashcards

71 test answers

Unlock all answers in this set

Unlock answers 71
question
John Dalton's Atomic Theory
answer
1. Elements: are composed of extremely small particles called atoms. All atoms of a given element are identical, having the same size, mass, and chemical properties. The atoms of one element are different from the atoms of all other elements

2. Compounds: are composed of atoms of more than one element. In any compound, the ratio of the numbers of atoms of any two of the elements present is either an integer or a simple fraction. (incorporates laws of definite proportions and multiple proportions)
a. Law of definite proportions: different samples of the same compound always contain its constituent elements in the same proportions by mass.
b. Law of multiple proportions: If two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in ratios of small whole numbers (use CO and CO2 as an example: 12 to 16 versus 12 to 32.)
c. Law of conservation of mass: matter can be neither created nor destroyed

3. A chemical reaction involves only the separation, combination, or rearrangement of atoms; it does not result in their creation or destruction.
question
Atom
answer
the basic unit of an element that can enter into chemical combinations
question
Atoms composed of ____, _______, and _______.
answer
electrons

protons

neutrons
question
charge and mass of electrons
answer
negatively charged

mass= 9.1096 x 10^-31 kg
question
charge and mass of protons
answer
positively charged

mass= 1.6727 x 10^-27 kg
Unlock the answer
question
charge and mass of neutrons
answer
neutral

mass= 1.6750 x 10^-27 kg
Unlock the answer
question
3 kinds of particles and/or radiation emitted by radioactive substances
answer
alpha particles (helium nuclei)

beta (?) particles (electrons)

gamma rays
Unlock the answer
question
Atomic number
answer
Z

number of protons in nucleus= number of electrons in a neutral atom
Unlock the answer
question
mass number
answer
A

sum of protons plus number of neutrons in nucleus
Unlock the answer
question
Element
answer
a form of matter in which all of the atoms have the same atomic number
Unlock the answer
question
isotopes
answer
when two atoms have the same number of protons but a different number of neutrons

Therefore, two atoms of the same element can have different mass numbers
Unlock the answer
question
Special names 1A
answer
alkali metal
Unlock the answer
question
Special names 2A
answer
alkaline earth metals
Unlock the answer
question
special names 7A
answer
halogens
Unlock the answer
question
special names 8A
answer
noble gases
Unlock the answer
question
Molecule
answer
an aggregated of at least two atoms in a definite arrangement held together by chemical forces (bonds)
Unlock the answer
question
7 diatomic elements
answer
H, N, O, F, Cl, Br, I

H2, N2, O2, F2, Cl2,Br2, I2 diatomic
Unlock the answer
question
Ion
answer
charged species formed from a neutral atom or molecule when electrons are gained or lost as a result of a chemical change
Unlock the answer
question
cations
answer
positive
Unlock the answer
question
anions
answer
negative
Unlock the answer
question
Chemical Formulas
answer
express the composition of molecules and ionic compounds in terms of chemical symbols
Unlock the answer
question
Molecular formula
answer
shows the exact number of atoms of each element in the smallest unit of a substance

EX: Methane = CH4
Unlock the answer
question
Allotrope
answer
one of two or more forms of an element

Ex: oxygen, O2 and ozone, O3
Unlock the answer
question
Empirical formula
answer
tells which atoms are present and the simplest whole number ratio of the atoms (determined by experiment)

glucose contains C, H, O in 1:2:1 ratio
therefore the empirical formula is CH2O
Unlock the answer
question
ionic compounds
answer
discrete molecules are not present; ionic compounds are represented by their empirical formulas
Unlock the answer
question
Four types of compounds
answer
1. ionic
2. molecular (covalent)
3. acids
4. bases, hydrates
Unlock the answer
question
mono-
answer
1
Unlock the answer
question
di-
answer
2
Unlock the answer
question
tri-
answer
3
Unlock the answer
question
tetra-
answer
4
Unlock the answer
question
penta-
answer
5
Unlock the answer
question
hexa-
answer
6
Unlock the answer
question
hepta-
answer
7
Unlock the answer
question
octa-
answer
8
Unlock the answer
question
nona-
answer
9
Unlock the answer
question
deca-
answer
10
Unlock the answer
question
acid
answer
a substance that yields hydrogen ions (H+) when dissolved in water
Unlock the answer
question
oxoacids
answer
acids that contain hydrogen, oxygen, and another element
Unlock the answer
question
base
answer
a substance that gives hydroxide anions (OH-) when dissolved in water
Unlock the answer
question
hydrates
answer
compounds that have a specific number of water molecules attached

EX: BaCl2•2 H2O barium chloride dihydrate

Sr(NO3)2•4 H2O strontium nitrate tetrahydrate
Unlock the answer
question
hydrocarbons composed of what?

Alkanes
answer
composed of carbon and hydrogen

CnH(2n+2)

CH4= methane
C2H6=ethane
C3H8=propane
C4H10=butane
C5H12=pentane
C6H14=hexane
C7H16=heptane
C8H18=octane
C9H20=nontane
C10H22=decane
Unlock the answer
question
NH4+
answer
ammonium
Unlock the answer
question
H3O+
answer
hydronium
Unlock the answer
question
Hg2 2+
answer
mercury I
Unlock the answer
question
CN-
answer
cyanide
Unlock the answer
question
OCN-
answer
cyanate
Unlock the answer
question
SCN-
answer
thiocyanate
Unlock the answer
question
OH-
answer
hydroxide
Unlock the answer
question
C2H3O2-
answer
acetate
Unlock the answer
question
MnO4-
answer
permanganate
Unlock the answer
question
NO3-
answer
nitrate
Unlock the answer
question
NO2-
answer
nitrite
Unlock the answer
question
H2PO4-
answer
dihydrogen phosphate
Unlock the answer
question
HCO3-
answer
hydrogen carbonate or bicarbonate
Unlock the answer
question
HSO4-
answer
hydrogen sulfate
Unlock the answer
question
HSO3-
answer
hydrogen sulfite
Unlock the answer
question
ClO4-
answer
perchlorate
Unlock the answer
question
ClO3-
answer
chlorate
Unlock the answer
question
ClO2-
answer
chlorite
Unlock the answer
question
ClO-
answer
hypochlorite
Unlock the answer
question
O2 2-
answer
peroxide
Unlock the answer
question
C2O4 2-
answer
oxalate
Unlock the answer
question
CrO4 2-
answer
chromate
Unlock the answer
question
Cr2O7 2-
answer
dichromate
Unlock the answer
question
HPO4 2-
answer
hydrogen phosphate
Unlock the answer
question
CO3 2-
answer
carbonate
Unlock the answer
question
SO4 2-
answer
Sulfate
Unlock the answer
question
SO3 2-
answer
sulfite
Unlock the answer
question
S2O3 2-
answer
thiosulfate
Unlock the answer
question
PO4 3-
answer
phosphate
Unlock the answer
question
AsO4 3-
answer
aresenate
Unlock the answer
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New