Modules 14, 15 Matter & Atoms

atom

the smallest particle of an element that has the properties of that element

electron

negatively charged subatomic particle that is moving around outside the nucleus of an atom; very little mass

element

a pure substance made of one kind of atom

matter

Anything that has mass and takes up space

neutron

the subatomic particle located in the nucleus that has no charge

nucleus

The central core of an atom made up of protons and neutrons; most of the mass of an atom but small volume

proton

positively charged subatomic particle in the nucleus of an atom

atomic number

An atom's number of protons. Whole number shown on the periodic table.

isotopes

Atoms of the same element (same number of protons) that have different numbers of neutrons and therefore a different mass number

ion

Positively or negatively charged particle due to atoms losing or gaining electrons

valence electrons

Electrons on the outermost energy level of an atom

neutral atom

atom with equal number of protons and electrons; the positive charge cancels out the negative charge

mass number

the total number of protons and neutrons in a nucleus

subatomic particles

Particles that make up atoms: protons, neutrons, electrons

electron cloud

a region outside of the nucleus of an atom where electrons are likely to be found; lots of empty space, very little mass

isotope notation

notation that shows the chemical symbol, mass number, and atomic number for an atom of an element

group

a vertical column in the periodic table that contains elements having similar physical and chemical properties

ion charge

An electric charge that forms on an atom when it gains or loses valence electrons. Getting more electrons makes - ions, losing electrons makes + ions.

Compound

A substance made up of atoms of two or more different elements joined by chemical bonds

heterogeneous mixture

a mixture in which the composition is not uniform throughout

homogeneous mixture (solution)

A mixture in which substances are evenly distributed throughout the mixture

pure substance

A sample of matter, either a single element or a single compound, that has definite chemical and physical properties

signs of a chemical change

color change, odor change, gas production, energy change, formation of a precipitate, light emitted

Flammability is a ___ property

chemical

melting point is a __property

physical

You find a year-old

Little Debbie snack cake and eat it anyway. What results in this bad flavor?

chemical change

How can you find the number of neutrons in an atom?

mass number minus atomic number

How many neutrons does Carbon-14 have?

8

What is the mass number of Oxygen-16?

16

What is the atomic number of Fluorine-19?

9

If an atom has 9 protons, 10 neutrons, and 9 electrons, what is the overall charge?

neutral, no charge

If an atom has 7 protons, 7 neutrons, and 10 electrons, what is the overall charge?

3-

If an atom has lost one valence electron, what is the overall charge?

1+

What type of change occurs when ice melts and becomes water?

physical change

What type of change occurs when diesel burns?

chemical change

How many electrons does an atom of Na¹⁺ have?

10

How many total electrons does an atom of Cl¹⁻have?

18

According to the law of conservation of mass, the total mass of the reacting substances is

equal to the mass of the products

How do you find the melting point on a heating curve?

Horizontal portion of the graph between the solid phase and the liquid phase

Which portion of a heating curve shows a gas increasing in temperature?

the top right region

Which portion of a heating curve shows a solid increasing in temperature

the bottom left region

The starting materials in a chemical reaction are called the

reactants

The substances produced in a chemical reaction are called

products

NaCl and water stirred together is a

mixture of compounds

Carbon dropped into a beaker with Sulfur and Copper is a

mixture of elements

H₂SO₄ is a

compound

What is sublimation?

the process in which a solid changes directly into a gas

What is condensation?

The change of state from a gas to a liquid

What is vaporization?

the change from a liquid to a gas

What is melting?

The change in state from a solid to a liquid

According to the kinetic-molecular theory, when the temperature is lowered, the particles of matter

vibrate more slowly

When the temperature of a substance increases, the particles

vibrate more quickly

How many valence electrons does carbon have?

4

Fe or Ni being attracted to a magnet is an example of a

physical property

If 16 grams of CH₄ reacts completely with

64 grams of O₂, what mass of products

should form?

80 g

If 34 g of hydrogen peroxide decomposes, what mass of products will form?

34 g