Level 1 Chemistry: Chemical World

These flashcards cover foundational chemistry concepts including atomic structure, ions, chemical equations, combustion, acids and bases, and various types of chemical reactions as presented by Mr. Hooper.

What are the three particles that make up an atom?

Protons, neutrons, and electrons.

Where is the nucleus located in an atom?

The centre of the atom.

What is the mass and charge of a proton?

A mass of $1\,amu$ and a charge of $+1$.

What is the mass and charge of a neutron?

A mass of $1\,amu$ and a charge of $0$.

What is the mass and charge of an electron?

A negligible mass (approx. 2000 times smaller than protons/neutrons) and a charge of $-1$.

What determines an element's unique atomic number?

The number of protons in its nucleus.

How is the mass number of an atom defined?

The number of protons AND neutrons an element has in its nucleus.

According to the 'Aufbau' principle, how do electrons fill shells?

Electrons fill up 'shells' or 'energy levels' from the lowest level up.

What is the rule for filling up electron shells for the first 20 elements?

$2, 8, 8, 2$.

What is an ion?

A charged atom that has lost or gained electrons to have a complete outer shell.

What is the naming convention for negative monoatomic ions?

The end of the name is replaced with '-ide' (e.g., Chlorine becomes chloride).

What are polyatomic ions?

Ions that are made up of multiple different kinds of atoms.

What must the total charge of ions combine to in a neutral ionic compound?

The charges must combine to equal $0$.

What does the Law of Conservation of Mass state?

Matter cannot be created or destroyed.

In balancing chemical equations, what numbers are you allowed to change?

Only the big numbers in front of a molecule; you cannot add small numbers to change molecules.

What is a combustion reaction?

A reaction between a fuel and oxygen that gives off heat and light energy.

What are the specific products of complete combustion?

Carbon dioxide ($CO_2$) and water ($H_2O$).

What are the common products of incomplete combustion?

Carbon monoxide ($CO$), Carbon (soot), and water ($H_2O$).

How can you test for the presence of Carbon Dioxide ($CO_2$)?

Pass the gas through limewater (calcium hydroxide solution); it will turn cloudy and form a milky white precipitate.

How can you test for the presence of water ($H_2O$)?

Use blue cobalt chloride paper, which turns pink if it reacts with water.

Why is Carbon Monoxide ($CO$) dangerous to humans?

It binds to haemoglobin in the blood, reducing the amount of oxygen that can be transported around the body.

What defines a substance as an acid?

Substances that contain $H^+$ (Hydrogen) ions and dissociate when added to water.

What is the difference between a strong acid and a weak acid?

Strong acids completely dissociate in water, while weak acids only partially dissociate.

What ion is formed when an alkali dissociates in water?

$OH^-$ (hydroxide) ions.

What does the pH scale measure and what are its ranges?

It describes how acidic or basic a molecule is from $0$ to $14$ ($7$ is neutral, below $7$ is acidic, above $7$ is basic).

How does litmus paper react to acidic and basic solutions?

Acidic solutions turn blue litmus red; basic solutions turn red litmus blue.

What is a neutralisation reaction?

A chemical reaction between an acid and a base to form a salt and water.

What is the general equation for a reaction between an acid and a metal carbonate?

$\text{acid} + \text{metal carbonate} \rightarrow \text{salt} + \text{water} + \text{carbon dioxide}$.

What is a combination reaction?

A reaction involving two or more reactants combining to form one larger product.

What is a decomposition reaction?

A reaction involving one reactant decomposing to form two or more products.

What is thermal decomposition?

A decomposition reaction that occurs in the presence of heat.

What is a precipitation reaction?

A reaction that occurs when two ionic solutions are mixed and an insoluble product (a precipitate) forms.

Under what condition will a solute dissolve in a solvent?

When the forces of attraction between the solute and solvent are greater than the forces holding the solute particles together.

In chemical notation, what do the subscripts (s) and (aq) represent?

(s) means the substance is a solid, and (aq) means it is dissolved in water (aqueous).