Teas 7 Chemistry Practice Question

Solid to Liquid

Melting (absorbs energy)

Liquid to Solid

Freezing, (releases energy)

Liquid to Gas

vaporization/absorbs energy

Gast to Liquid

condensation/ release energy

Gas to Solid

deposition/ release energy

Solid to Gas

sublimation

Matter

Anything that takes up space

Mass

the amount of matter in an object

How Does Matter Change?

Matter usually changes state when you add or take away heat, which changes the temperature of the matter

Substance

A single kind of matter that is pure and has a specific set of properties.

examples of substances

1. Water

2. Alcohol

3. Oil

4. Food coloring

Solids

The particles in solids are tightly packed

Liquids

Liquids are also a condensed phase, however, in contrast to solids, the particles have some translational kinetic energy, which means they have freedom to move

gas phase

the phase of matter in which atoms or molecules can move essentially independently of one another

Which state(s) of matter take the shape of their container?

Liquids and gases take the shape of their containers since, they do not have definite shape and volume. Only solids have definite shape and volume.

SOLIDS

have the least volume

LIQUIDS

have a definite volume

GASES

have maximum volume

Which of the following is correct?

(a) Solids have a definite shape and definite volume.

(b) Liquids have a definite volume but no definite shape.

(c) Gases have a definite volume but no definite shape.

(d) Liquids have both definite shape and definite volume.

(a) Solids have definite shape and definite volume.

(b) Liquids have definite volume but no definite shape.

Which state of matter has atoms that move freely?

Gas

Which state of matter has atoms that can slide past each other?

Liquid

Which state of matter has atoms that vibrate in place?

Solid

Solute

A substance that is dissolved in a solution.

Solvent

the substance in which the solute dissolves

Solution

A homogeneous mixture of two or more substances

Osmosis

Diffusion of water through a selectively permeable membrane

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

Osmosis

Diffusion of water through a selectively permeable membrane

Atom

The smallest component and the most basic part of matter that still retains its identity

Atomic structure

Atoms have a nucleus and electrons. Its nucleus contains protons and neutrons

Nucleus

The part of the atom that houses the protons and the neutrons

Protons

positively charged subatomic particles

Neutrons

the particles of the nucleus that have no charge. they are neutral and without a positive or negative electrical charge; the part of the atom that gives the atom its isotope identity.

Electrons

The part of the atom that has a negative (-) charge

Ion

An electrically charged atom

Cation

A positively charged ion

Anion

A negatively charged ion

Plasma

Plasma is not naturally found in nature on our earth. Instead, plasma is produced artificially or it is found beyond our atmosphere and universe.

The Properties of Substances

The unique and distinctive properties of substances differentiate them from other substances with their own unique and distinctive properties.

Density

mass/volume

Volume

The amount of space an object takes up

Boiling point

the temperature at which a substance changes from a liquid to a gas

Melting point

The temperature at which a solid becomes a liquid

Conductivity

The ability of an object to transfer heat or electricity to another object.

Heat capacity

the number of heat units needed to raise the temperature of a body by one degree.

Malleability

the ability of a substance to be hammered or beaten into thin sheets

What is a physical property?

a characteristic that can be observed or measured without changing the identity of the substance

What is cellular transport?

the movement of molecules in/out of cells to keep cells alive and maintain homeostasis

Cellular transport is split into two categories

a. Active transport

b. Passive transport

What is active transport?

the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy. ACTIVE=ENERGY

What is passive transport?

The movement of materials across the cell membrane without using cellular energy. PASSIVE=NO ENERGY

What is diffusion?

The movement of particles from an area of high concentration to an area of low concentration.

What is an example of Diffusion?

For example, when you add a drop of food coloring to water, immediately, the food coloring begins to spread (or diffuse) throughout the water, eventually reaching equilibrium where all areas have the same concentration of coloring:

What is a concentration gradient?

difference in the concentration of a substance from one location to another

What is Kinetic Energy?

the energy an object has due to its motion.

An example of kinetic energy is

running water

KCl is an example of which type of bond?

ionic

What is an ionic compound?

Ionic compounds are compounds made up of ions that form charged particles when an atom (or group of atoms) gains or loses electrons. A cation is an ion charged positively; an anion is an ion charged negatively.

What is an ionic bond?

Formed when one or more electrons are transferred from one atom to another.

Which of the following is exchanged between two or more atoms that undergo ionic bonding?

Valence electrons

What is an ion?

Ions are formed when an atom gains or loses electrons

What is a negative ion?

A negative ion is created when an atom gains electrons. Electrons have a negative charge.

What is a positive ion?

A positive ion is created when an atom loses electrons. Electrons have a negative charge.

What is a chemical bound?

1. Atoms of the same element may bond together to form molecules or crystalline solids.

2. involves atoms combining to form chemical compounds and bring stability to the resulting product. I

What is a valence electrons?

electrons in the outermost shell

How do you find the number of protons?

Look at the atomic number it is the same.

How do you find the number of electrons?

same as the number of protons.

How to find the number of neutrons in an atom?

To find the number of neutrons, you will need to subtract the atomic number from the atomic mass. Remember that the atomic number is the same as the number of protons, which you have already identified

Where can I find the atomic number of an element?

The atomic number is located above the element symbol.

Where can I find the atomic mass of an element?

The atomic mass can be found underneath the symbol for the element.

What is an electrical charge?

For example, if we have an object made up of 14 protons, which are positive, and 12 electrons, which are negative, then we end up with a net charge of positive 2. We simply add 1 for each proton and subtract 1 for each electron. If the resulting number is positive, we have a net positive charge and if the resulting number is negative, we'll have a net negative charge. Note that neutral particles will make no difference in the net charge.

What does combustion produce?

energy, carbon dioxide, and water

Covalent bonds

are in many biological compounds, including lipids and carbohydrates.

Ionic bounds are found in what elements?

Ionic bonds form only between metals and nonmetals. That's because metals "want" to give up electrons, and nonmetals "want" to gain electrons.

(found in salts)

Hydrogen bounds are found in what elements?

Hydrogen bonding occurs only in molecules where hydrogen is covalently bonded to one of three elements: fluorine, oxygen, or nitrogen

A graduated cylinder is used to measure;

Large amounts of volume

Measuring spoons are used to measure;

Small amounts of liquid

Volumetric pipettes are used to measure;

Used to measure small amounts of water

Volumetric flasks are used to measure;

Large amounts of liquid

What is the equation for 'parts per million"

(amount of solute/amount of solution) x 1.0 x 10^6

Which of the following can change with pressure?

a. Adhesion

b. Boiling Point

c. Luster

d. Cohesion

Water's boiling point depends on the pressure!

Chlorine is a

nonmetal

Beryllium is a

Alkaline Earth Metal

Neon is a

nonmetal

acid-base reaction

When an acid and base mix together, neutralize one another's properties, and form a salt.