Chemistry Fundamentals & Periodicity Practice Flashcards

These flashcards cover fundamental chemistry concepts from the lecture notes, including atomic structure, periodic trends, chemical bonding, reactions, and the factors affecting reaction rates.

According to the transcript, where are metals and non-metals located on the Periodic Table?

Metals are on the left and Non-metals are on the right.

How is an atomic mass unit (amu) defined in the notes?

$1/12$ the mass of a carbon atom.

What are the relative masses and charges of the three subatomic particles?

Proton: Mass $1$, Charge $+1$; Neutron: Mass $1$, Charge $0$; Electron: Mass $0$, Charge $-1$.

Which subatomic particle determines the type of an atom?

The atomic number, which is the number of protons.

For an atom with 79 protons and a mass number of 197, how many neutrons does it have?

$118$ neutrons ($197 - 79 = 118$).

What is the rule for the maximum number of electrons in the first three shells?

The first shell can hold $2$ electrons, the second shell can hold $8$, and the third shell (for the 3rd period) can hold up to $8$.

What is the electronic configuration of Lithium ($Li$)?

$$Li = 2,1$$

What happens to the atomic radius and atomic mass as you move down Group 1?

Both atomic radius and atomic mass increase as you go down the group.

What is the trend for melting and boiling points in Group 1 as you go down the group?

Both melting points and boiling points decrease as you go down Group 1.

What is the trend in color for Group 7 (Halogens) as you move down the group?

The color of the element darkens (Fluorine: Yellow, Chlorine: Green, Bromine: Orange-brown, Iodine: Purple).

What are the boiling points for Fluorine and Chlorine according to the table?

Fluorine: $-188\text{ }^\text{o}C$; Chlorine: $-35\text{ }^\text{o}C$.

Why do atomic radius and mass increase down every group in the periodic table?

Radius increases due to the extra electron shell; mass increases due to extra protons and neutrons.

Why is a sodium ion ($Na^+$) positively charged?

It still has $11$ protons but now has only $10$ electrons after losing one to achieve a full outer shell.

How are negative ions named relative to their element names?

The name is similar to the element but ends in $-ide$ (e.g., chlorine atoms form chloride ions).

What holds atoms together in an ionic bond?

Electrostatic attraction between ions of opposite charges, such as $Na^+$ and $Cl^-$.

Why do ionic compounds have high melting points?

They form a crystal lattice where strong ionic bonds act in all directions, requiring a large amount of energy to break.

When do ionic compounds conduct electricity?

They do not conduct when solid, but they do conduct when in solution or when molten.

Why are Group 8 (noble gases) elements so unreactive?

They have a full outer shell of electrons, which is stable.

What is a covalent bond?

A bond formed when atoms share a pair of electrons, holding atoms together and forming a molecule.

How many covalent bonds are formed in an oxygen molecule ($O_2$) and a nitrogen molecule ($N_2$)?

Oxygen forms $2$ covalent ($O=O$) bonds and nitrogen forms $3$ covalent bonds.

How many covalent bonds are Carbon ($C$) and Silicon ($Si$) capable of forming?

They are capable of forming $4$ covalent bonds.

What are allotropes?

Different forms of the same element in the same state, such as diamond and graphite for Carbon.

Why can graphite conduct electricity while diamond cannot?

In graphite, each carbon atom has only $3$ covalent bonds, meaning one electron is delocalised and free to move.

What is a displacement reaction?

A reaction where a more reactive metal displaces a less reactive metal from a compound.

What are the chemical formulas for Hydrochloric acid, Nitric acid, and Sulphuric acid?

Hydrochloric acid: $HCl$; Nitric acid: $HNO_3$; Sulphuric acid: $H_2SO_4$.

What are the general products of the reaction between a metal carbonate and an acid?

$$\text{Salt} + \text{Water} + \text{Carbon Dioxide}$$

How is the name of a salt determined?

The first part comes from the metal (or alkali) and the second part comes from the acid (e.g., zinc + sulfuric acid = zinc sulfate).

What is the difference between a base and an alkali?

Bases are substances that neutralise acids to produce salt and water; alkalis are bases that dissolve in water.

How is the average rate of reaction calculated from volume and time?

$$\text{Rate} = \frac{\text{increase in volume (cm}^3\text{)}}{\text{time interval (s)}}$$

Why does the rate of reaction decrease over time on a graph?

The concentration of reactants is reducing as they get used up, leading to a lower frequency of collisions.

Define Independent, Dependent, and Controlled variables.

Independent: The one thing you change; Dependent: What you measure/observe; Controlled: Constants kept the same.

How does surface area affect the rate of reaction?

As surface area increases, the rate of reaction increases because more collisions occur per second on the surface of the solid.

What effect does a $10\text{ }^\text{o}C$ increase in temperature usually have on the rate of reaction?

For most reactions, the rate doubles for every $10\text{ }^\text{o}C$ increase in temperature.

Why does increasing temperature increase the reaction rate?

It increases the kinetic energy of particles, resulting in more frequent collisions and collisions with enough energy to break bonds.