CHEM 1020 (Chapter 1)

Am

Americium

a colorless gas that cannot be separated into simpler substances using physical means and that reacts with the metal magnesium to produce both a magnesium oxygen compound and a magnesium-nitrogen compound homogeneous mixture element heterogeneous mixture compound

compound note: Compound. The sample is not a mixture; it cannot be separated by physical means. It reacts with magnesium (an element) to form two compounds containing different elements. Therefore, the sample contains more than one element; it is a compound.

One substance present, three phase present, substance cannot be decomposed using chemical means. compound mixture element

element note: A substance that cannot be decomposed by chemical means is an element.

One substance present, one phase present, substance cannot be decomposed using chemical means. element mixture compound

element note: Element. A substance that cannot be decomposed by chemical means is an element.

One substance present, three phase present, substance cannot be decomposed using chemical means. element mixture compound

element note: Element. A substance that cannot be decomposed by chemical means is an element.

Substance A cannot be broken down into simpler substances by chemical means.... compound element classification not possible

element note: Substance A is an element. An element is a pure substance that cannot be broken down into simpler pure substances by chemical means such as a chemical reaction, an electric current, heat, or a beam of light.

T/F.... In order for matter to be heterogeneous, at least two compounds must be present.

false note: In order for matter to be heterogeneous, at least two substances (either elements or compounds) must be present.

T/F... A compound results from the physical combination of two or more elements.

false note: A compound results from the chemical combination of two or more elements.

T/F.... Current chemical theory suggests there are more naturally occurring elements yet to be discovered.

false note: Any elements discovered in the future will be highly unstable and thus not naturally occurring.

T/F.... Helium is the second-most abundant element in Earth's crust.

false note: Helium is the second most abundant element in the universe not in Earth's crust.

T/F.... Oxygen and silicon are the two most abundant elements in the universe.

false note: Oxygen and silicon are the most abundant elements in Earth's crust not in the universe.

T/F.... In a compound containing mercury and sulfur, physical methods can be used to separate the substances present.

false note: The elements in a compound are chemically combined and cannot be separated by physical methods.

Gd

gadolinium

Au

gold

three substances present, three phases present... pure substance homogeneous mixture heterogeneous mixture

heterogeneous mixture Note: Heterogeneous mixture. The existence of three substances in three different phases indicates that the substances are not mixed uniformly.

Two substances present, two phases present compound mixture element

mixture note: Two substances are mixed together; this is a mixture.

Three elements present, composition is variable. compound mixture element

mixture note: Mixture. Since the composition is variable, this is not a compound; it is a mixture.

Two substances present, one phase present.... element compound mixture

mixture note: Mixture. Two substances are mixed together; this is a mixture.

Os

osmium. element note: because only one type of atom is present

Butter melts when placed in the sun.... physical chemical

physical

Lead is a soft metal... chemical property physical property

physical property Note: The hardness of a substance is a physical property.

Rn

radon

Si

silicon

Zr

zirconium

Which is the best description of the sample (diamond) shown here? a pure substance a homogeneous mixture a heterogeneous mixture

A pure substance Note: Diamond is made of a single element with a single, consistent structure. It is a pure substance.

is the same for the gaseous and solid states? shape no common physical characteristics volume

no common physical characteristics Note: Solids and gases have no common physical characteristics.

P4

phosphorus element note: element cause only one type of Atom is present. element All four atoms present are the same kind, phosphorus.

Moisture that begins to collect on the outside of a cold glass is a .............. process.

physical Note: because it involves the change of gaseous water to liquid water.

Mercury is a liquid at room temperature... chemical property physical property

physical property Note: The states of matter are physical properties.

One substance present, two phases present pure substance homogeneous mixture heterogeneous mixture

pure substance Note: Pure substance. The two phases present represent two forms of a single substance (for example, ice and liquid water).

T/F.... Two elements account for more than three-fourths of the atoms in Earth's crust.

true note: Both oxygen and silicon constitute 80.2% of all atoms in Earth's crust.

T/F.... In a compound containing mercury and sulfur, the two elements are chemically combined rather than physically combined.

true note: Elements in a compound are chemically combined.

T/F.... Hydrogen is the most abundant element in both Earth's crust and the universe.

true note: Hydrogen is the most abundant element in the universe not in Earth's crust.

T/F.... In a mixture of mercury and sulfur, the two elements maintain their individual properties.

true note: The two elements are physically combined and retain their physical properties.

T/F.... Elements that do not occur in nature have been produced in a laboratory setting.

true note: There are a number of heavier elements that do not occur naturally.

T/F.... A mixture containing mercury and sulfur can have a variable composition.

true note: Variable composition is one indication of a mixture.

Which is the best description of the sample (potassium dichromate) shown here? a pure substance a homogeneous mixture a heterogeneous mixture

Pure substance note: This sample of potassium dichromate is not mixed with any other substances. It is a single chemical compound, so it is a pure substance.

Ag

Silver

One substance present, three phase present, substance cannot be decomposed using chemical means.... element compound mixture

elements note: Element. A substance that cannot be decomposed by chemical means is an element.

T/F.... More laboratory-produced elements exist than naturally occurring elements.

false note: There are 88 naturally occurring elements.

T/F.... At present, 108 elements are known.

false note: there are a total of 110 elements known

Two substances present, two phases present... pure substance homogeneous mixture heterogeneous mixture

heterogeneous mixture Note: Heterogeneous mixture. "Two substances" makes this a mixture; "two phases" shows that it is not uniformly mixed.

water and oil... classify its category and number of phases.. pure substance homogeneous mixture heterogeneous mixture

heterogeneous mixture Phase: 2 note: Heterogeneous mixture, two phases. The two liquids are not soluble in one another; they are separate phases.

a "cloudy" liquid that separates into two layers upon standing overnight.... homogeneous mixture element heterogeneous mixture compound

heterogeneous mixture note: Heterogeneous mixture. A "cloudy" mixture is not homogeneous; it has two phases.

Which is the best description of the sample (potassium dichromate dissolved in water) shown here? a pure substance a homogeneous mixture a heterogeneous mixture

a homogeneous mixture Note: This sample of potassium dichromate is dissolved in water. It is a mixture of the two compounds, water and potassium dichromate. Because potassium dichromate is dissolved evenly in the water, any portion of the sample is identical to any other. Therefore, this is a homogeneous mixture.

The process of sublimation of iodine. a physical property a physical change a chemical property a chemical change

a physical change Note: The process of sublimation of iodine is physical change. Iodine sublimation is a change of state. No new substance is produced.

a nonuniform, white crystalline substance, part of which dissolves in alcohol and part of which does not dissolve in alcohol homogeneous mixture element heterogeneous mixture compound

heterogeneous mixture note: Heterogeneous mixture. The sample is nonuniform; it is heterogeneous.

Two substances present, one phase present pure substance homogeneous mixture heterogeneous mixture

homogeneous mixture Note: Homogeneous mixture. "One phase" indicates that the mixture of two substances has uniform properties throughout.

a blue-colored, single-phase liquid that when boiled away (evaporated) leaves behind a solid residue... homogeneous mixture element heterogeneous mixture compound

homogeneous mixture note: Homogeneous mixture. The sample is a single phase (homogeneous); when it is boiled away (evaporated), it reveals that there are two substances (a mixture).

Three elements present, composition is variable... element compound mixture

mixture note: Mixture. Since the composition is variable, this is not a compound; it is a mixture.

Zn

zinc

Which is the best description of the sample (water) shown here? Consider only the contents of the glass, not the glass or the container. Assume that the water has nothing dissolved in it. a pure substance a homogeneous mixture a heterogeneous mixture

a pure substance NOte: Water is composed of O and H atoms, but they are always combined in the same compound. If nothing is dissolved in the water then it is a pure substance and always has the same composition and the same properties.

Ba

barium

distinguishes gases from solids? volume both volume and shape shape

both volume and shape Note: Gases have an indefinite volume and indefinite shape; solids have a definite volume and definite shape.

Plants use carbon dioxide from the air to make sugar... physical chemical

chemical

digestion of a baked potato... chemical process physical process

chemical process Note: Digestion is a chemical transformation; potato becomes a new chemical substance.

rusting of an iron bridge... chemical process physical process

chemical process Note: The chemical combination of oxygen and iron forms rust (Fe2O3).

The fuels in the space shuttle (hydrogen and oxygen) combine to give water and provide the energy to lift the shuttle into space.... chemical property physical property

chemical property Note: The fuel produces a new substance and energy, indicating a chemical property.

Substance B cannot be broken down into simpler substances by physical means.... compound element classification not possible

classification not possible note: Classification is not possible because not enough information is given.

Substance D readily reacts with the element chlorine.... compound element classification not possible

classification not possible note: classification not possible due to lack of enough info

Substance C readily dissolves in water.... compound element classification not possible

classification not possible Note: classification not possible due to lack of enough info

Bi

Bismuth

SF6

Sulfur hexafluoride compound note: two types of atoms are present

The process of boiling water. a physical property a physical change a chemical property a chemical change

a physical change Note: The process of boiling water is physical change. Water boiling is a change of state. No new substance is produced.

The fact that metallic gold is a solid at room temperature. a physical change a physical property a chemical change a chemical property

a physical property Note: The fact that metallic gold is a solid at room temperature is physical property. The state (solid) of a substance (gold) is a physical property.

At

astatine

Ca

calcium

burning of a wooden stick... chemical process physical process

chemical process

One substance present, two elements present. compound mixture element

compound note: A compound is a substance that contains more than one element.

One substance present, three elements present.... element compound mixture

compound note: Compound. A compound is a substance that contains more than one element.

A mixture contains the following five pure substances: S8, C2H6, C2H2, NH2OH, CH3OH. How many different kinds of atoms are present in this mixture?

5 S8 - 1 C2H6 - 2 C2H2 - 3 NH2OH - 4 CH3OH - 5

Classify each of the following as matter or energy (nonmatter).A rock matter energy

Matter Note: Matter is anything that has mass and occupies space.Strong nuclear force is energy.

homoatomic molecule

One kind of atom presents.

heteroatomic molecule

Two kinds of atoms present.

Table sugar: 12 C atoms, 22 H atoms, and 11 O atoms.

C12H22O11

Caffeine: 8 C atoms, 10 H atoms, 4 O atoms, and 2 N atoms.

C8H10O4N2

CaO

Calcium oxide compound

CO

Carbon monoxide compound

COS

Carbonyl sulfide Compound

Burning wood to release heat is a ........... process.

Chemical Note: because it involves converting wood to carbon dioxide and water.

KF

Potassium fluoride compound note: compound because there are two types of atoms present.

what is Gravity? matter energy

Energy Note: Matter is anything that has mass and occupies space.Gravity is energy.

Strong nuclear force matter energy

Energy Note: Matter is anything that has mass and occupies space.Strong nuclear force is energy.

T/F..... Substances maintain their identity in a heterogeneous mixture but not in a homogeneous mixture.

False Note: Substances maintain their identity in all mixtures; they are physically mixed, not chemically combined.

T/F.... Compounds, but not elements, can have a variable composition.

False note: Both compounds and elements have a definite composition.

T/F.... All heterogeneous mixtures must contain three or more substances.

False. Note: A heterogeneous mixture contains two or more substances.

water, ice, and oil... classify its category and number of phases... pure substance homogeneous mixture heterogeneous mixture

Heterogeneous mixture phases: 3 Note: Heterogeneous mixture, three phases. The three phases present are ice (solid), liquid water, and liquid oil. The two liquids are not soluble in one another; they are separate phases.

HCl

Hydrogen chloride Compound Note: cause there are two atoms present

Iron hammer... It takes the shape of its container and has a definite volume. It does not take the shape of its container and has a definite volume. It does not take the shape of its container and has an indefinite volume. It takes the shape of its container and has an indefinite volume.

It does not take the shape of its container and has a definite volume. Note: Iron hammer is a solid. It does not take the shape of its container; yes, it has a definite volume.

Nitrogen gas... It takes the shape of its container and has a definite volume. It does not take the shape of its container and has a definite volume. It does not take the shape of its container and has an indefinite volume. It takes the shape of its container and has an indefinite volume.

It does not take the shape of its container and has a definite volume. Note:Nitrogen is a gas. It has neither a definite shape nor a definite volume. It takes the shape and volume of its container.

Blood... It takes the shape of its container and has a definite volume. It does not take the shape of its container and has a definite volume. It does not take the shape of its container and has an indefinite volume. It takes the shape of its container and has an indefinite volume.

It takes the shape of its container and has a definite volume. Note: Blood is a liquid. It takes the shape of its container. It has a definite volume.

Granulated sugar... It takes the shape of its container and has a definite volume. It does not take the shape of its container and has a definite volume. It does not take the shape of its container and has an indefinite volume. It takes the shape of its container and has an indefinite volume.

It takes the shape of its container and has a definite volume. Note: Each granule of sugar has its own definite shape; however, the granules are small, so the general shape of the mass of crystals does take the shape of the container. Granulated sugar has a definite volume.

What is A spoon... matter energy

Matter Note: Matter is anything that has mass and occupies space.A spoon is matter.

T/F... Both elements and compounds are pure substances.

True note: An element contains one kind of atoms and so is a single pure substance. A compound has a definite, constant composition, so it is also a pure substance.

T/F..... Pure substances cannot have a variable composition.

True Note: A pure substance contains only one substance, and so has a definite composition

T/F... Pure substances are seldom encountered in the "everyday" world.

True Note: Most substances in the "everyday" world are mixtures.

Which is the best description of the sample (a chocolate chip cookie) shown here? a pure substance a homogeneous mixture a heterogeneous mixture

Two substances present, one phase present pure substance homogeneous mixture heterogeneous mixture Note: The cookie clearly has different composition in different areas. This means it is a heterogeneous mixture.

The process of burning coal. a physical property a chemical change a chemical property a physical change

a chemical change Note: The process of burning coal is chemical change. Burning coal produces new substances.

Which is the best description of the sample shown here? Consider only the contents of the glass, not the glass or the container. a pure substance a homogeneous mixture a heterogeneous mixture

a heterogeneous mixture Note: The soda water in the glass is a heterogeneous mixture because the solution (the liquid) and the carbon dioxide bubbles are in different phases. One part of the mixture is not like all the other parts, so this is a heterogeneous mixture.

Which is the best description of the sample shown above? a pure substance a homogeneous mixture a heterogeneous mixture

a heterogeneous mixture Note: This sample is a mixture of different solids. Because the sample is different in different places, it is a heterogeneous mixture.