physical science midterm

The first step in the scientific method is usually

Making an observation

What is an example of a physical change?

Melting ice

How many significant figures are in 7.357

4

Carbon and other nonmetals are found in which area of the periodic table

Right side of the periodic table

The chemical formula of water H2O means that each water molecule contains?

Two hydrogen atoms and one oxygen atom

After formulating a question, the next step of the scientific method is

Forming a hypothesis

A precise measurement is one that

Is repeated and consistent

Matter is defined as anything that

Has mass and takes up space

Which element is a semiconductor?

Silicon

Digesting food is an example of

A chemical change

Which unit is used to measure the height of a book case

Meters

A measurement that is accurate is one that

Is close to the true value

Solid liquids and gases are three forms of matter that

Have different physical states

Group 17 elements form

Halogens

What is a mixture?

Sand and water

7,300,000,000 is equal to

7.3 × 10^7 cm

How many significant figures should you show in your answer?

2

Ice, float, and water because

It is less dense than liquid water

Most elements are

Metals

What causes a chemical change?

Burning

What is equal to 0.0000075 g

7.5 × 10^-6 g

The resistance of a fluid to flow is referred to as

Viscosity

The law of conservation of mass states that mass cannot be

Created or destroyed

Most elements on the left side of the periodic table

Are metals

What is an example of a chemical change?

Rusting iron

You put one spoonful of salt into one liter of water the resulting liquid is an example of

A solution

Temperature is a measure of the average___ energy of the particles in the object

Kinetic

Buoyant force is the ___ force exerted on an object immersed or float floating on a liquid

Upward

Most nonmetals are

Brittle

A chemical change occurs whenever

New substances are formed

What determines the speed of the atoms and molecules of a particular substance?

Temperature

The change of a substance from a solid directly to a gas is called

Sublimation

Elements that share properties of both metals and nonmetals are called

Metalloids

What is true of noble gases

They readily react with other elements

What is the density of a sample of liquid that has a volume of 15 mL in a mass of 10 g ( d = m/v)

0.67 g/mL

According to the kinetic theory of matter. What makes matter true

Particles are always in motion

When ice melts to form liquid energy

Is absorbed

Group 18 Noble gases are relatively inert because

Their outer energy levels are full

What is not a part of Dalton’s atomic theory?

Atoms can be divided

Helium is used in balloons because

It is less dense than air

A measure of the average kinetic energy of the particles in an object is known as

Temperature

The temperature at which a substance changes from a liquid to a solid is

The freezing point

Two different isotopes of an element have different

Numbers of neutrons

A subatomic particle that has a negative charge is called

An electron

The mass of a 2 L sample of gas with the density of 8.0 mg/L is (m =d x v )

16 mg

The process of a liquid becoming a gas is called

vaporization

A substance changes from a liquid to a gas during evaporation because

Particles gain enough energy to escape

An atom’s mass number equals the number of

Protons + neutrons

An electron jumps to a new energy level when

It absorbs energy

Which of the following is not a fluid?

Solid

A gas becomes a liquid through a process called

Condensation

How does the density of an object that sinks into a fluid compared to the density of the fluid?

It’s more dense than the fluid

What is mendeleev known for?

Creating the periodic table

Elements within the same group in the periodic table have similar properties because they have the same number

Of valence electrons

The science of what matter is made of and how it changes is called

Chemistry

Is energy matter

No

A substance that cannot be broken down into smaller substances is

An element

An ionic bond is a bond that forms between

A metal and a nonmetal

In which type of bond do atoms share electrons

Covalent bond

A compound differs from a mixture because it has

A fixed composition

Copper atoms are held together by___bonds

Metallic

The atoms will form a ____ bond by ___ their electrons

Ionic and transferring

When two oxygen atoms bond, they will form a___ bond by ___ their electrons

Covalent, sharing

Atoms often join so that each atom will have

A full outer energy level

The name for the compound with the formula Cr2O3 would be written as

chromium (lll) oxide

A covalent compound made of one sulfur and two oxygen atoms would be named

Sulfur dioxide

The chemical formula for an ionic compound of potassium and oxygen is

K2O

A compound is held together by

Chemical bonds

The name for the compound with the formula CuBr2 would be written as

Copper(ll) bromide

The name dinitrogen tetroxide tells you that this compound contains

Two nitrogen atoms and four oxygen atoms

What is a homogeneous mixture?

Air

What is a solution?

Salt water

Pennies minted after 1984 contain 97.5% zinc and 2.5% copper these coins are example examples of

Alloys

An oatmeal raisin cookie is an example of

Heterogeneous mixture

The Tyndall effect is observed in

Colloids

A molecule that has partially changed positive and negative areas is

Polar

What is an example of a heterogeneous mixture

Oil and water

You can usually separate out a suspension by

Filtering

You can make a salad dissolve more quickly than a liquid by

Stirring, heating, or crushing

What will make it easier to dissolve a solid in a liquid?

Cooling the liquid