Atomic structure, chemical bonding, chemical equations, elements, compounds and mixtures

Question 1

What subatomic particle(s) is/are found in the nucleus?

Answer 1

Protons and neutrons.

Question 2

What is the relative mass of an electron?

Answer 2

1/1836

Question 3

What is the relative mass of a proton?

Answer 3

1

Question 4

What is the relative mass of a neutron?

Answer 4

1

Question 5

What is the relative charge of a proton?

Answer 5

1+ / positive

Question 6

What is the relative charge of a neutron?

Answer 6

No charge / neutral

Question 7

What is the relative charge of an electron?

Answer 7

1- / negative

Question 8

What are isotopes?

Answer 8

Isotopes refer to atoms of an element that have the same number of protons but a different number of neutrons.

*Tip to remember this more easily;
Isotopes <> neutrons {Just memorise the subatomic particle that is different}

Question 9

What are ions?

Answer 9

An ion has the same number of protons and neutrons as an atom of the same element but has a different number of electrons.

*Tip to remember this more easily;
Ions <> electrons {Just memorise the subatomic particle that is different}

Question 10

What are cations?

Answer 10

Cations are positively charged ions and are produced when the atoms lose electrons.

Question 11

What are anions?

Answer 11

Anions are negatively charged ions and are produced when the atoms gain electrons.

Question 12

What is ionic bonding?

Answer 12

Ionic bonding involves the formation of ions as a result of atoms gaining or losing electron(s) in order to obtain the electronic configuration/structure of a noble gas.

Question 13

Metals __________ (gain/lose/share) electrons.

Answer 13

Lose

~Maybe remember it as ML; mobile legends changed to metal loses?

Question 14

Non-metals __________ (gain/lose/share) electrons.

Answer 14

Gain

~Maybe remember it as NMG; not my giraffe changed to non-metal gains?

Question 15

What is the structure of a solid ionic compound?

Answer 15

A giant lattice structure which is held together by strong electrostatic forces of attraction.

Question 16

Why do ionic compounds have high boiling and melting points.

Answer 16

A lot of energy is required to overcome the strong electrostatic forces of attraction that hold the ions in the lattice.

Question 17

Why are ionic compounds excellent conductors of electricity in molten or aqueous state?

Answer 17

When in molten or aqueous state, ionic compounds form mobile ions that can move freely and conduct electricity as they act as charge-carriers.

Question 18

Why are ionic compounds non-conductors of electricity in their solid state?

Answer 18

When in solid state, the cations and the anions are held together by strong, electrostatic forces of attraction and cannot move about freely to conduct electricity.

Question 19

What is covalent bonding?

Answer 19

Covalent bonding forms when an electron pair is shared by both atoms in order to obtain the electronic configuration/structure of a noble gas.

Question 20

Covalent bonds can be __________.

1. Single
2. Double
3. Triple
4. All of the above
5. None of the above

Answer 20

Answer is 4. All of the above.

Question 21

What is the structure of covalent molecules?

Answer 21

Covalent molecules can be held together by strong covalent bonds (within the molecules) and weak intermolecular forces (between the molecules).

Question 22

What kind of structures do covalent molecules have?

Answer 22

Simple molecular structure or giant molecular structure.

Question 23

What is the simple molecular structure?

Answer 23

The molecules are held together by weak intermolecular forces.

Question 24

Why do simple molecular substances have low boiling and melting points?

Answer 24

During melting and boiling, the intermolecular covalent bonds are not being broken. Only the much weaker intermolecular forces are overcome. Thus, very little energy is required.

Question 25

Why are simple molecular substances non-conductors of electricity?

Answer 25

There are no free and mobile electrons or ions to carry the electric charges.

Question 26

Simple molecular substances are soluble in 1.__________ but insoluble in 2.________.

Answer 26

1. Organic solvents (solvents that contain carbon)

2. Water

Question 27

Element composition.

Answer 27

Only one type of atom.

Question 28

Element bonding.

Answer 28

Simple covalent bonds exist between a molecule of an atom.

Question 29

Element purity.

Answer 29

Pure, fixed melting and boiling points.

Question 30

Element properties.

Answer 30

Unique set of properties.

Question 31

Element separation.

Answer 31

Cannot separate. (nothing to separate -_-)

Question 32

Examples of elements.

Answer 32

Sodium (Na)
Gold (Au)
Etc.

Question 33

Compound composition.

Answer 33

Two elements or more.

Question 34

Compound bonding.

Answer 34

Chemically bonded by ionic or covalent bonds in a fixed ratio.

Question 35

Compound purity.

Answer 35

Pure, fixed melting and boiling points.

Question 36

Compound properties.

Answer 36

Own set of properties. (completely different from the elements it is made up of)

Question 37

Compound separation.

Answer 37

Can only be separated by chemical processes. (thermal decomposition/electrolysis)

Question 38

Examples of compounds.

Answer 38

Table salt (sodium+chloride {NaCl})
Water (hydrogen+oxygen {H2O})
Etc.

Question 39

Mixture composition.

Answer 39

Made up of at least two or more substances. (elements and/or compounds)

Question 40

Mixture bonding.

Answer 40

Not chemically bonded in any ration.

Question 41

Mixture purity.

Answer 41

Impure, a range of melting and boiling points.

Question 42

Mixture properties.

Answer 42

Retains all the properties of the compounds and/or elements it is made up of.

Question 43

Mixture separation.

Answer 43

Separated easily by physical means;

1. Crystallisation
2. Distillation
3. Evaporation to dryness
4. Fractional distillation
5. Paper chromatography

Question 44

Examples of mixture.

Answer 44

Sea water (salt+water) ➡️  Made up of compounds
Air (nitrogen+oxygen+carbon dioxide+methane+argon+neon+hydrogen+a bunch of other gases) ➡️ Made up of elements and compounds.

Question 45

Cations that have to be memorised.

Answer 45

Hydrogen <> H+
Sodium <> Na+
Potassium <> K+
Ammonium <> [NH4]+
Silver <> Ag+
Calcium <> Ca2+
Magnesium <> Mg2+
Zinc <> Zn2+

{write out these chemical names to remember how they are supposed to look like more easily}
*There are no brackets in the original writings.

Question 46

Anions that have to be memorised.

Answer 46

Oxide <> O2-
Nitrate <> [NO3]-
Hydroxide <> [OH]-
Sulfate <> [SO4]2-
Carbonate <> [CO3]2-

{write out these chemical names to remember how they are supposed to look like more easily}
*There are no brackets in the original writings.

Question 47

Chemical equations.

Answer 47

Remember the state symbols;

(g) ➡️ Gas
(l) ➡️ Liquid
(s) ➡️ Solid
(aq) ➡️ Aqueous

Steps in constructing balanced equations;

1. Know the reactants and their resulting products.
2. Write the equation as [reactants → products] using their chemical formula names.
3. Balance the equation by only writing the number in front of the various chemical names to ensure that there is the same number of each type of atom before and after the reaction.
4. Add a state symbol to each chemical in the final equation.

Question 48

I will now_________ (pass/fail/get full marks for/get an egg for) chemistry.

Answer 48

Maybe a fail if you are lucky and maybe an egg if you are not. 🤪