Chapter 2 workbook questions

What is the result of -8 divided by -2?

4

What is a mixture?

A mixture is a combination of two or more different substances which I mix but not combined chemically. The ratios of the substances in a mixture can be arbitrary.

Define precipitate

A precipitate is a solid that forms and settles out of a liquid mixture.

What is True about all physical changes that involve a change of state?

All the physical changes that involve a change of state are physical changes, they can be classified as reversible or irreversible.

How does an extensive property differ from an intensive property?

An extensive property depends on how much matter there is. An intensive property depends of what type of matter it is.

Stibium is the Latin name for which element?

Antimony

What is the symbol for gold?

Au

Compounds are substances that can be separated into simpler substances only by ------ means

Chemical

What are chemical symbols used for?

Chemical symbols are used to help write chemical formulas of compounds

A physical change it alters a given material without changing its chemical what?

Composition

Subscripts in chemical formulas are used to indicate the relative proportions of the elements in a

Compound

Sodium chloride is a ------ of sodium which is a soft ------ and chlorine which is a pale yellow -------

Compound; metal; gas

The law of conservation of mass states that any physical change or chemical reaction, mass is neither ------- nor --------

Created; destroyed

In general what is used to separate mixtures?

Differences in properties of the components of the mixture determine the method used to separate the mixture in general.

What happens to during distillation

Distillation is a method of separating the components of a liquid mixture (the components should have a boiling part points far apart.)

What happens during a chemical reaction

During chemical reaction one or more substances will change into another substance

Each ------ has a unique set of properties

Element

Is the following sentence true or false? All samples of a substance have different physical properties.

False

Is this following statement true or false? If you observe a clue for chemical change, you can be certain that a chemical change has taken place.

False

Is the following sentence true or false? Elements can be easily separated into simpler substances.

False (elements cannot be separated into smaller, simpler substances. They are already in the smallest form)

Is the following sentence true or false? The words gas and vapor describe the same thing.

False (gas and vapor cannot be used interchangeably. Gas is a physical state while vapor is not a physical state. Vapor is a substance diffused in the air)

The process that separates a solid from a liquid in a heterogeneous mixture is called

Filtration

List for possible clues that chemical change.

For clues to a chemical change include one transfer of energy to production of gas three changing color and four formation of a precipitate.

Match each arrangement of particles in matter with a physical state; gas, liquid, solid a. Packed tightly together b. Close, but free to follow c. Spaced relatively far apart

Gas;c Liquid;b Solid;a

Define a gas' properties; shape, volume, can be compressed.

Gases have an indefinite shape, indefinite volume, and can easily be compressed.

Is brain paper a physical change or chemical change? How do you know?

I chemical change, because papers identity is altered and burning paper cannot be reversed.

What is a chemical property?

I chemical property is the ability for a substance to undergo certain specific chemical changes.

Describe one way to decide whether a sample of matter is a substance or mixture.

If the composition of a chemical symbol is fixed, then samples is a substance. However if the composition of a sample varied, then the sample is a mixture.

What is used to represent an element?

In element can be represented with a one or two letter chemical symbol. For instants carbon is represented C while sodium is represented as Na

PB is the symbol for what element?

Lead

Define a liquid's properties; shape, volume, can be compressed.

Liquids have a definite volume, indefinite shape, and are not easily compressed.

The ash produced by the burning paper has much less mass than the mass of the original paper was the mass conserved during the change?explain your answer

Mass was conserved because ash and gases were produced and those also have mass. The total of the paper and oxygen equals the total mass of the ash and gas. However you cannot really see the mass of gas that's why the products less than the reactants.

A physical property is a quality or condition of the substance that can be ----------- or ----------- without changing the substance's

Observed; measured

What are some words that describe physical changes?

Physical change words include boil, melt, break, dissolve, condense, etc.

During a chemical reaction the mass of a products is always equal to the mass of the

Reactants

In chemical reactions the substances present at the start of the reaction are called ----------, and substances produced are called ---------

Reactants; products

The term gas is limited to those substances that exist in the gaseous state at

Room temperature (gases will exist in the gaseous state at room temperature)

Define a solids properties; shape, volume, can be compressed.

Solids have a definite shape, definite and are not easily compressed

Matter that has a uniform and definite composition is called a

Substance

In what two groups can substances be classified

Substances can be classified as compounds or as elements

What of an object is a measure of the amount of matter the object contains?

The mass

How do you know that mass was conserved

The mass of the product equals the mass of the reactants

If you said the change(burning paper) this chemical, what are the reactants? What are the product?

The reactants are paper and oxygen in the products are ash and gas

Is the following sentence true or false? A heterogeneous mixture is one that has a completely uniform composition

True

Is the following sentence true or false? Chemical properties are observed only when a substance undergoes a chemical change.

True

Is the following sentence true or false? Most samples of matter are mixtures.

True

Is the following sentence true or false? Physical properties can help a chemist identify a substance.

True

Is the following sentence true or false? The elements that make up a compound are always present in the same proportions

True

Is the following sentence true or false? The properties of compounds are different from those of the component elements

True ( properties of compounds are different from component elements. For instance water consist of two hydrogen atoms and one oxygen atom)

What does vapor describe

Vapor is the gaseous state of a substance that is a solid or liquid at room temperature.

List the letter of the term that is not a physical property. a. Hardness b. Color c. Boiling point d. Melting

a. Melting (Melting is not a physical property. Hardness, color and boiling point are physical properties because they can all be observed and/or measured without manipulating the composition of the substance.)

How many phases exist in these types of mixtures a. Homogeneous b. Heterogeneous

a. Single phase b. Contains more than one phase

List the letter of the term that describes a part of a sample having uniform composition and parts. a. Solution b. Mixture c. State d. Phase

a. Solution

List the letter of the substance that is a yellow solid and melts at 115°C a. Sulfur b. Chlorine c. Gold d. Copper

a. Sulfur

List the letter of the term that is not a physical shape of matter. a. Water b. Gas c. Liquid d. Solid

a. Water

Which representation of a chemical reaction is correct a. products-reactants b. reactants-products

b. reactants-products

Circle the letter of the term that best completes the sentence. A change in the composition of matter --------- occurs during a chemical reaction a. Sometimes b. Rarely c. Always d. Never

c.always

What is another name for a homogeneous mixture

solution

What is the result of -7+ -10 minus -3?

-14

What is the result of -4×4?

-16

Which number is larger -234 or -250?

-234

What is the melting point of bromine?

-7