Elements, Compounds, and Mixtures

Comprehensive review flashcards covering the definitions, macroscale and microscale models, physical and chemical properties, separation techniques, and classifications of elements, compounds, and mixtures.

Pink Sands Beach in the Bahamas gets its pale pink sand from microscopic coral insects called __________ that leave red shells behind.

Homotrema rubrum

The jet-black sand on Hawaii's black sand beaches is formed from basalt created when __________ hits the ocean.

lava

The scale of matter that describes visible properties such as color, texture, state of matter, and total mass that can be seen directly with the naked eye is the __________.

macroscale

The scale of matter at the level of atoms and molecules that requires models or microscopes to describe is the __________.

microscale

In this particle model showing blue diatomic molecules and red single atoms unbonded together, the matter is classified as a(n) __________.

mixture

In this particle model showing only one type of identical gray spherical atom, the matter is classified as a(n) __________.

element

In this particle model showing identical molecules each composed of one black atom bonded to two white atoms, the matter is classified as a(n) __________.

compound

A mixture of iron filings and sand can be physically separated using a magnet because the iron and sand retain their original __________ properties.

physical

A pure substance made of only one kind of atom that cannot be broken down into simpler substances by ordinary chemical reactions is a(n) __________.

element

Properties such as density, melting point, boiling point, and reactivity that do not depend on the amount of material and are used to identify matter are called __________ properties.

characteristic

Cobalt has a melting point of $1{,}495\,^\circ\text{C}$ and a density of __________$\,\text{g/cm}^3$.

$$8.9$$

Unlike cobalt and nickel, iron combines slowly with oxygen in the air to form __________.

rust

Elements that are shiny, malleable, ductile, and good conductors of thermal energy and electric current are classified as __________.

metals

Solid nonmetals tend to be dull, poor conductors, and __________, meaning they shatter easily.

brittle

Elements that have properties of both metals and nonmetals and are also referred to as semiconductors are called __________.

metalloids

The metalloid widely used to manufacture computer chips is __________.

silicon

The chemical symbol for gold, $\text{Au}$, is derived from its Latin name __________.

aurium

The chemical symbol for sodium, $\text{Na}$, is derived from its Latin name __________.

natrium

The physical separation method where liquid turns into gas, leaving behind dissolved solid crystals, is called __________.

evaporation

The physical separation method that uses a mesh screen to separate smaller particles from larger ones is a(n) __________.

sieve

The device that uses rapid spinning to separate substances such as whole blood into red blood cells and liquid plasma based on different densities is a(n) __________.

centrifuge

In a mixture, substances are physically blended together and are __________ chemically bonded.

not

A compound is a pure substance composed of two or more different elements that are chemically combined in a definite or fixed __________.

ratio

Molecules that consist of two identical atoms of the same element chemically bonded together, such as $\text{O}_2$ or $\text{N}_2$, are known as __________ molecules.

diatomic

As illustrated below, table salt has properties that are completely __________ the individual properties of sodium metal and toxic chlorine gas.

different from

Water can be chemically broken down into hydrogen gas and oxygen gas by passing a(n) __________ through it in an electrolytic cell.

electric current

In a chemical formula, the small number placed below the line that indicates the number of atoms of an element is the __________.

subscript

In the chemical expression $2\text{NH}_3$, the number $2$ placed before the formula is the __________, indicating the number of molecules present.

coefficient

Vitamin C ($\text{C}_6\text{H}_8\text{O}_6$) and rubbing alcohol ($\text{C}_3\text{H}_8\text{O}$) are completely different substances despite containing the same three elements because their atoms combine in different __________.

ratios

Air is categorized as a(n) __________ because it contains unbonded gases like $\text{N}_2$, $\text{O}_2$, and $\text{CO}_2$ floating together.

mixture