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

question

charge and mass of neutrons

answer

neutral

mass= 1.6750 x 10^-27 kg

question

3 kinds of particles and/or radiation emitted by radioactive substances

answer

alpha particles (helium nuclei)

beta (?) particles (electrons)

gamma rays

question

Atomic number

answer

Z

number of protons in nucleus= number of electrons in a neutral atom

question

mass number

answer

A

sum of protons plus number of neutrons in nucleus

question

Element

answer

a form of matter in which all of the atoms have the same atomic number

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

question

Special names 1A

answer

alkali metal

question

Special names 2A

answer

alkaline earth metals

question

special names 7A

answer

halogens

question

special names 8A

answer

noble gases

question

Molecule

answer

an aggregated of at least two atoms in a definite arrangement held together by chemical forces (bonds)

question

7 diatomic elements

answer

H, N, O, F, Cl, Br, I

H2, N2, O2, F2, Cl2,Br2, I2 diatomic

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

question

cations

answer

positive

question

anions

answer

negative

question

Chemical Formulas

answer

express the composition of molecules and ionic compounds in terms of chemical symbols

question

Molecular formula

answer

shows the exact number of atoms of each element in the smallest unit of a substance

EX: Methane = CH4

question

Allotrope

answer

one of two or more forms of an element

Ex: oxygen, O2 and ozone, O3

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

question

ionic compounds

answer

discrete molecules are not present; ionic compounds are represented by their empirical formulas

question

Four types of compounds

answer

1. ionic
2. molecular (covalent)
3. acids
4. bases, hydrates

question

mono-

answer

1

question

di-

answer

2

question

tri-

answer

3

question

tetra-

answer

4

question

penta-

answer

5

question

hexa-

answer

6

question

hepta-

answer

7

question

octa-

answer

8

question

nona-

answer

9

question

deca-

answer

10

question

acid

answer

a substance that yields hydrogen ions (H+) when dissolved in water

question

oxoacids

answer

acids that contain hydrogen, oxygen, and another element

question

base

answer

a substance that gives hydroxide anions (OH-) when dissolved in water

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

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

question

NH4+

answer

ammonium

question

H3O+

answer

hydronium

question

Hg2 2+

answer

mercury I

question

CN-

answer

cyanide

question

OCN-

answer

cyanate

question

SCN-

answer

thiocyanate

question

OH-

answer

hydroxide

question

C2H3O2-

answer

acetate

question

MnO4-

answer

permanganate

question

NO3-

answer

nitrate

question

NO2-

answer

nitrite

question

H2PO4-

answer

dihydrogen phosphate

question

HCO3-

answer

hydrogen carbonate or bicarbonate

question

HSO4-

answer

hydrogen sulfate

question

HSO3-

answer

hydrogen sulfite

question

ClO4-

answer

perchlorate

question

ClO3-

answer

chlorate

question

ClO2-

answer

chlorite

question

ClO-

answer

hypochlorite

question

O2 2-

answer

peroxide

question

C2O4 2-

answer

oxalate

question

CrO4 2-

answer

chromate

question

Cr2O7 2-

answer

dichromate

question

HPO4 2-

answer

hydrogen phosphate

question

CO3 2-

answer

carbonate

question

SO4 2-

answer

Sulfate

question

SO3 2-

answer

sulfite

question

S2O3 2-

answer

thiosulfate

question

PO4 3-

answer

phosphate

question

AsO4 3-

answer

aresenate

Chapter 2 from Chem 1303 – Flashcards

Unlock all answers in this set

Haven't found what you were looking for?

Search for samples, answers to your questions and flashcards