H Chemistry Fall Final

What are physical properties experienced with?

Normal senses such as touch, sight, and hearing.

Why is taste not considered a physical property?

It is a basic test for our environment and is technically a chemical experiment.

At what temperature does water boil?

100 degrees C / 212 degrees F.

What is the most important compound to exist?

Water.

What defines a chemical property of a substance?

A substance's ability to form new substances when heated or exposed to other substances.

What is a physical change?

A change in the state of matter where the substance remains the same in composition.

What happens to particles during a physical change?

Particles physically change location between them.

How can we categorize a solid?

A rigid substance with a fixed shape and volume.

What is a characteristic of a liquid?

Definite volume but takes the shape of the container.

What defines a gas?

Matter that has neither fixed volume nor fixed shape.

What is an alloy?

A mixture of metals.

What is the formula for converting Kelvin to Celsius?

C = K + 273.

Define matter. What two criteria does it fulfill?

Physical stuff that makes up the universe; it has mass and takes up volume.

What is an atom?

The basic piece that makes up all matter.

What are compounds made of?

Substances made by bonding different atoms together.

What are diatomic elements?

Elements that cannot exist on their own such as H, O, F, Br, I, N, Cl.

What is an isotope?

Same elements with different atomic masses.

What is the atomic mass?

The total number of protons and neutrons in an atom. (protons + neutrons)

What denotes a cation?

A positively charged ion due to losing electrons.

What is an anion?

A negatively charged ion due to gaining electrons.

What occurs when an ionic bond forms?

Oppositely charged ions are attracted to each other.

What is a chemical change?

A rearrangement of the elements present with no atoms lost or gained.

What does the law of conservation of matter state?

Matter cannot be created or destroyed, only rearranged.

What is a net ionic equation?

An equation that removes spectator ions from the overall reaction.

What is an electrolyte?

An aqueous solution of dissolved ions that can conduct electricity.

What occurs in an acid-base neutralization reaction?

Acid + Base ---> salt + water.

Define synthesis in chemical reactions.

The combination of two different elements to make a compound.

What type of reaction is C2H6 + O2 ---> CO2 + H2O?

Combustion reaction.

What is a limiting reactant?

The reactant that gets used up first, limiting the amount of product formed.

What is percent yield?

(actual yield / theoretical yield) x 100.

What is the empirical formula?

The simplest ratio of elements in a compound.

What is the molecular formula?

The actual composition of elements in a compound.

Define a homogenous mixture. Give an example.

A mixture with a uniform composition throughout; examples include milk and air.

Define a heterogeneous mixture. Give an example.

A mixture with variable composition; examples include salad and trail mix.

What happens during a redox reaction?

Electrons are transferred between substances.

What is a precipitate?

A solid that forms from a new ionic compound that is insoluble.

What is involved in the process of dissociation for acids?

An acid splits into H+ ions and a corresponding anion in solution.

What defines a pure substance?

A material with a consistent composition throughout.

What do the coefficients in a balanced equation represent?

The mole ratio of reactants and products during a chemical reaction.

What are spectator ions?

Ions that do not participate in a chemical reaction and are not part of the net ionic equation.

What is the difference between actual yield and theoretical yield?

Actual yield is the amount obtained from an experiment, while theoretical yield is the amount calculated based on starting amounts.

What is the relationship between temperature and the state of matter?

Temperature affects whether certain materials are in solid, liquid, or gas states.

Name the three common states of mater. Which involves the least energy?

Solid, liquid, gas; solid involves the least energy.

What is the metric prefix for one billion?

Giga-.

In the periodic table, what are groups/families?

Columns that contain elements with similar properties.

What are periods in the periodic table?

Rows that show elements with increasing atomic numbers.

What does the electron cloud model describe?

The probable locations of electrons around the nucleus.

What role do neutrons play in the atom?

They contribute to the atomic mass and stabilize the nucleus.

What do you call the number of protons in an atom?

Atomic number.

How do you convert Farenheit to Celsius?

C = (F - 32) x 5/9.

What do you call the combination of two substances that releases energy?

Exothermic reaction.

What characterizes an endothermic reaction?

It absorbs heat from the surroundings.

What is boiling point?

The temperature at which a substance changes from liquid to gas.

What happens to energy during chemical changes?

Energy is either released or absorbed.

Define the term 'molar mass'.

The mass of one mole of a substance, usually in grams per mole.

What happens during the process of condensation?

Gas turns into liquid as it cools.

What did Democritus contribute to atomic theory?

He proposed the idea of indivisible particles called atoms.

What identifies a substance as a metal?

It is usually malleable, conductive, and has luster.

What distinguishes non-metals from metals?

Non-metals are usually brittle, not conductive, and dull.

What do you call a mixture of metals?

An alloy.

What property do noble gases exhibit?

They are typically unreactive due to their complete valence electron shell.

What is a solute?

The substance that is dissolved in a solution.

What is a solvent?

The substance that does the dissolving in a solution.

What is the characteristic of a binary acid?

It has 'H' in front of its formula and contains only two different elements.

What are oxyacids?

Acids that contain hydrogen, oxygen, and another element.

What will mixing steel wool and vinegar produce?

A chemical reaction will occur with observable signs.

What is the significance of the atomic mass unit?

It is a standard unit of mass that quantifies atoms.

What is the formula for calculating percent composition?

% composition = ([mass of element]/[total molar mass]) x 100.

How do you find the empirical formula?

Convert mass to moles, select the smallest mole count, and divide by it.

What is a molecule?

Atoms that are bonded together.

What defines a pure substance?

A material made of only one type of particle.

What can affect the rate of a chemical reaction?

Concentration, temperature, surface area, and catalysts.

What is a predicting product in a chemical reaction?

Products are the substances formed as a result of a chemical reaction.

What is meant by limiting reactant in a chemical reaction?

The reactant that is completely consumed first in a reaction, limiting the amount of product formed.

How can you determine the limiting reactant?

By calculating the moles of reactants and identifying which one produces the least amount of product.

What is the significance of determining limiting reactants?

It helps to predict the maximum amount of products that can be formed in a reaction.

What happens if there is an excess of reactant?

The excess reactant remains unreacted at the end of the reaction.

What is stoichiometry?

The calculation of reactants and products in chemical reactions based on the balanced equation.

How do you predict the products of a combustion reaction?

Combustion of hydrocarbons typically produces carbon dioxide and water.

What are spectator ions in the context of limiting reactants?

Ions that do not affect the equilibrium of the reaction and do not change during the reaction.