Success Criteria Checklist

You've got a brilliant roadmap here that covers all the essential chemistry concepts you'll need to master. Think of this as your personal progress tracker - it's designed to help you identify exactly where you stand with each topic.

The checklist covers four major areas: reaction rates, atomic structure, chemical bonding, and calculations. Each skill builds on the previous ones, so don't worry if some areas feel trickier than others - that's completely normal!

Use the tick, question mark, and cross system honestly. Being realistic about what you understand now will help you focus your revision time where it's needed most.

Top Tip: Come back to this checklist regularly as you study - watching those crosses turn into ticks is incredibly motivating!

Reaction Rates Fundamentals

Ever wondered why some chemical reactions happen instantly whilst others take ages? Reaction rate measures how quickly reactants disappear and products form - and you can actually control this speed.

Three main factors affect how fast reactions occur. Concentration matters because more particles in a smaller space means more collisions. Temperature speeds things up because particles move faster and collide more energetically. Surface area increases reaction rate because there's more contact between reactants.

Catalysts are like chemical cheat codes - they speed up reactions without getting used up themselves. They remain completely unchanged at the end, so you can use them again and again.

Real-world connection: This explains why food cooks faster at higher temperatures and why powdered medicine works quicker than tablets!

Measuring and Calculating Reaction Rates

You can monitor reactions by tracking changes in mass, volume, or concentration over time. The key equation you need is: Average rate = Change in measurable quantity ÷ Change in time.

Rate graphs tell the whole story of a reaction. The steeper the line, the faster the reaction. When the line goes horizontal, the reaction has stopped completely. You can read off how much product formed and exactly when the reaction finished.

Comparing multiple experiments on the same graph shows you which conditions make reactions faster. The purple line beating the blue line? That's your higher temperature or increased concentration in action.

Units matter! If you're measuring mass, your rate will be in g/s (grams per second). For volume changes, use cm³/s (cubic centimetres per second).

Exam tip: Always check your units match the measurement you're tracking - it's an easy way to pick up marks!

Atomic Structure and the Periodic Table

The periodic table organises all 118 known elements by atomic number and groups elements with similar properties together. It's like a massive family tree where relatives share characteristics.

Atoms contain three types of particles. Protons $positive charge, mass = 1$ and neutrons $no charge, mass = 1$ live in the central nucleus. Electrons (negative charge, almost no mass) whizz around in shells outside the nucleus.

Here's the crucial bit: atoms are electrically neutral because they have equal numbers of protons and electrons. The positive and negative charges cancel each other out perfectly.

Groups in the periodic table have predictable properties. Group 1 metals are soft and reactive. Group 7 halogens are reactive non-metals. Group 0 noble gases barely react with anything.

Memory trick: Think of the atom like a football stadium - the tiny nucleus is the centre circle, whilst electrons fill the stands around it!

Atomic Numbers and Electron Arrangements

Every element has a unique atomic number - that's the number of protons in its atoms. Since atoms are neutral, the atomic number also tells you the number of electrons.

Mass number equals protons plus neutrons. To find neutrons: Mass number - Atomic number = Number of neutrons. Nuclide notation shows this clearly with mass number top-left and atomic number bottom-left of the element symbol.

Electron arrangements follow specific rules. The first shell holds 2 electrons maximum, the second holds 8, the third holds 8, and the fourth holds 2. You'll find these arrangements listed in your databook for the first 20 elements.

Sodium (11 electrons) arranges as 2,8,1. Oxygen (8 electrons) arranges as 2,6. These arrangements determine how elements behave chemically.

Study smart: Don't memorise all the electron arrangements - learn the shell capacity rules and you can work them out!

Isotopes and Bonding Basics

Isotopes are atoms of the same element with different numbers of neutrons. Carbon-12 and Carbon-14 both have 6 protons but different mass numbers due to extra neutrons.

Relative atomic mass (RAM) accounts for all isotopes of an element. If chlorine's RAM is 35.5, then chlorine-35 must be more common than chlorine-37 (because the average is closer to 35).

Atoms bond to achieve stable electron arrangements - basically, they want full outer shells. They can lose, gain, or share electrons to get there, creating two main bond types: covalent and ionic.

Think of bonding like atoms trying to feel complete. They'll do whatever it takes to fill their outer electron shells!

Key insight: The drive for stability explains all chemical bonding - atoms are just trying to achieve their most comfortable state.

Covalent Bonding

Covalent bonds form when two non-metal atoms share electrons. It's like a chemical handshake where both atoms benefit from the shared pair.

The seven diatomic elements (I Bring Clay For Our New House: I₂, Br₂, Cl₂, F₂, O₂, N₂, H₂) naturally exist as molecules with covalent bonds between identical atoms.

In hydrogen gas (H₂), each hydrogen shares its single electron, giving both atoms a full outer shell. In methane (CH₄), carbon shares electrons with four hydrogens, satisfying everyone's needs.

Double bonds $like O=O$ and triple bonds (like N≡N) form when atoms share multiple electron pairs. More shared electrons mean stronger bonds.

Visual learner tip: Draw out the electron sharing diagrams - seeing how electrons pair up makes covalent bonding click instantly!