Unit 1 - Stoichiometry Vocabulary

Stoichiometry Vocabulary Flashcards

Stoichiometry

The calculation of reactants and products in chemical reactions

Element

A pure substance made of only one type of atom

Compound

A substance made from two or more elements chemically bonded in fixed ratios

Mixture

A combination of two or more substances that are not chemically bonded

Homogeneous Mixture

A mixture with uniform composition throughout

Heterogeneous Mixture

A mixture with non-uniform composition; different parts are visible

Mole (mol)

A unit representing 6.02 × 10²³ particles of a substance

Avogadro’s Number

6.02 × 10²³ particles per mole

Relative Atomic Mass (Ar)

The weighted average mass of an atom compared to 1/12 of carbon-12

Relative Formula Mass (Mr)

The sum of the relative atomic masses of the atoms in a formula

Molar Mass (M)

The mass of one mole of a substance, in grams/mol

Chemical Equation

A representation of a chemical reaction using symbols and formulas

Balancing Equations

Ensuring the same number of atoms of each element on both sides of the equation

State Symbols

Abbreviations indicating physical state: (s) solid, (l) liquid, (g) gas, (aq) aqueous

Empirical Formula

The simplest whole-number ratio of elements in a compound

Molecular Formula

The actual number of atoms of each element in a molecule

Atom Economy

(desired product mass / total product mass) × 100

Solid

State of matter with fixed shape and volume

Liquid

State of matter with fixed volume but no fixed shape

Gas

State of matter with neither fixed shape nor volume

Sublimation

Change of state from solid directly to gas

Deposition

Change of state from gas directly to solid

Boiling

Vaporization throughout a liquid at a specific temperature

Evaporation

Vaporization at the surface of a liquid below boiling point

Diffusion

The spreading of particles from high to low concentration due to random motion

Law of Conservation of Mass

In a chemical reaction, mass is conserved; Atoms are neither created nor destroyed

Combustion

Chemical + O2 → CO2 + H2O

Decomposition

One compound breaks down into a simpler substances

Synthesis

Two elements/ Compounds combine to form a compound

Single Replacement

AB + C → AC + B

Double Replacement

AB + CB → AC + BD

Neutralization

Acid + Base → Salt + Water

How to Find Moles

mass/ molar mass

How To Find Particles

Moles x (6.02 x 1023)

Atom Economy

(Mass of desired product/ total mass of products) x 100

Phlogiston Theory

An outdated theory; replaced by modern understand of combustion involving oxygen

Lavoisier

Introduced the Law of Conservation of Mass; Transformed chemistry into a quantitative science

How many moles are in 18.0 grams of water (H₂O)?

Aprox. 1 mol

What is the mass of 0.75 mol of sodium chloride (NaCl)?

43.83

How many molecules are in 0.50 mol of carbon dioxide (CO₂)?

3.01 x 10²³ g

How many atoms of hydrogen are there in 2.00 mol of H₂O?

2.41 × 10²⁴ atoms

If you have 4 mol of H₂, how many moles of O₂ are needed to react completely

2.0 mol O₂

If 5 mol of O₂ are available, how many moles of water can be formed?

10.0 mol H₂O

How many grams of water are produced from 2.5 mol of hydrogen gas?

45.05 g

How many grams of aluminum are needed to react with 71.0 g of chlorine gas (Cl₂)?

18.0 g

If 10.0 g of Al reacts, how many grams of AlCl₃ are produced?

49.4 g

1. Given 6.00 g of H₂ and 96.00 g of O₂, which are the limiting reactants?

(Use 2H₂ + O₂ → 2H₂O)

In the above reaction, how many grams of water will be produced?

H₂ is limiting

53.5g

1. A sample of hydrated copper(II) sulfate (CuSO₄·xH₂O) is heated. If the initial mass is 3.60 g and after heating it's 2.29 g, determine the value of x in the formula.

CuSO₄·5H₂O