AP Chemistry - Part 2 Brief

The Greek thinker who first suggested matter is made of indivisible "atomos" was __.

Democritus

The practice that dominated for nearly 2000 years before modern chemistry was __.

alchemy

The 17th-century scientist considered the first true chemist for using quantitative experiments was __.

Robert Boyle

The law stating that mass is neither created nor destroyed during a reaction is the Law of __.

Conservation of Mass

Proust’s principle that a compound always contains the same proportion of elements by mass is the Law of __.

Definite Proportion

Dalton’s rule about whole-number mass ratios in different compounds made from the same elements is the Law of __.

Multiple Proportions

According to Dalton, all atoms of a given element are __ to each other chemically.

identical

Dalton said that chemical reactions involve a __ of atoms, not their destruction.

reorganization

Gay-Lussac measured reacting gas __ under constant temperature and pressure.

volumes

Avogadro’s hypothesis states that equal volumes of gases at the same T and P contain equal numbers of __.

particles (molecules)

J. J. Thomson discovered the __ using cathode-ray tubes.

electron

Thomson measured the electron’s charge-to-mass ratio as __ C g⁻¹.

−1.76 × 10⁸

Thomson’s early atomic picture with electrons scattered in positive charge was the __ model.

plum pudding

Millikan’s oil-drop experiment determined the charge on a single __.

electron

The accepted mass of an electron is approximately __ kg.

9.11 × 10⁻³¹

Rutherford’s __ experiment showed that atoms have a tiny, dense, positive nucleus.

gold foil (alpha-particle)

In Rutherford’s model, over 99.9 % of an atom’s mass resides in the __.

nucleus

A proton’s charge is equal in magnitude but opposite in sign to that of an __.

electron

Neutral particles in the nucleus discovered by James Chadwick are called __.

neutrons

Atoms of the same element with different neutron numbers are called __.

isotopes

The isotope notation ⁴₂He shows a mass number of __.

4

Naturally occurring carbon is mainly __ with a smaller amount of carbon-13.

carbon-12

The only stable isotope of sodium is __.

sodium-23

A bond formed by sharing electrons between atoms is a __ bond.

covalent

A discrete group of covalently bonded atoms like CO₂ is called a __.

molecule

Attraction between oppositely charged ions produces an __ bond.

ionic

A positively charged ion formed by electron loss is a __.

cation

A negatively charged ion formed by electron gain is an __.

anion

The smallest whole-number ratio formula of an ionic compound is its __ formula.

empirical

Elements that commonly exist as diatomic molecules include H₂, N₂, O₂, F₂, Cl₂, Br₂, and __.

I₂

Vertical columns on the periodic table are called __.

groups or families

Group-1 elements typically form ions with a charge of __.

+1

Halide ions such as chloride and fluoride usually carry a charge of __.

−1

The cation is always named __ in a binary ionic compound.

first

A monatomic anion name is formed by adding the suffix __ to the element root.

-ide

When a metal can have multiple charges, its ionic charge is shown by a __ numeral.

Roman

The polyatomic ion with formula SO₄²⁻ is called __.

sulfate

The formula for ammonium nitrate is __.

NH₄NO₃

In naming binary covalent compounds, the prefix for six atoms is __.

hexa-

The compound N₂O₄ is named dinitrogen __.

tetraoxide (or tetroxide)

Arrhenius acids are recognized because their formulas begin with __.

H

The acid derived from nitrate (NO₃⁻) is __ acid.

nitric

To make carbonic acid neutral, two H⁺ ions combine with the carbonate ion, giving the formula __.

H₂CO₃

In the name chromium(II) oxide, the Roman numeral indicates the chromium ion has a charge of __.

+2