Chemistry Basics

Middle School (6-8) · Science

Chemistry Basics for grades 6-8 looks at what matter is made of and how it changes. Sessions work through atoms and their particles, how the periodic table is organised, how elements combine into compounds, and what actually happens during a chemical reaction. Because these lessons are spoken, the tutor asks the student to describe particle arrangements and reasoning out loud, and formulas like H2O or CO2 are read and spelled out piece by piece so subscripts don't get lost.

Start a session on Chemistry Basics

What this covers

  • Atomic structure: protons, neutrons and electrons, and reading atomic number and mass number off a periodic table square
  • Using the periodic table as a map - metals vs non-metals, groups vs periods, and why elements in the same column behave alike
  • Elements, compounds and mixtures: telling them apart and interpreting chemical formulas such as NaCl, CO2 and C6H12O6
  • The particle model of solids, liquids and gases, and explaining melting, freezing, evaporation and condensation in terms of particle motion and spacing
  • Physical vs chemical change, and identifying evidence of a reaction (gas bubbles, colour change, temperature change, precipitate)
  • Conservation of mass in a reaction, counting atoms on each side of an equation, and balancing simple equations
  • Acids, bases and the pH scale, including common household examples and what indicators show

Where learners get stuck

Treating dissolving as a chemical change
Sugar disappears into water, so it looks like something new was made. Students judge change by what they can see rather than by whether new substances with new properties formed - the sugar is still sugar and can be recovered by evaporation.
Mixing up subscripts and coefficients when counting atoms
In 2H2O the small 2 and the big 2 do different jobs, and spoken as 'two H two O' they sound the same. Students often add them or multiply the wrong pair, which then makes balancing equations feel arbitrary.
Thinking mass is lost when a reaction releases gas
A burning candle or a fizzing antacid tablet gets lighter on the scale, so mass appears to vanish. Students don't yet picture gas particles as having mass, so 'gone into the air' reads as 'gone'.
Saying an atom of oxygen and a molecule of oxygen are the same thing
Everyday language uses 'oxygen' for both. Without a clear habit of asking 'is this one atom or two joined together?', students write O when they mean O2 and misread formulas throughout.

What a session looks like

A session runs as a spoken back-and-forth. The tutor sets a starting question - say, why steam and ice are the same substance - and the student explains their thinking aloud while the tutor probes the gaps. Formulas, equations and periodic table entries appear on screen as they come up, and the student is asked to count atoms or predict a change before being told the answer. Sessions typically end with the student restating one idea in their own words.

Helpful to know first

  • Comfortable with whole-number multiplication and addition for counting atoms in formulas
  • Familiar with grams, millilitres and reading a simple measuring scale
  • Able to read information out of a table or grid
  • Some earlier exposure to solids, liquids and gases as the three common states of matter

Questions

Is this the same as physical science or chemistry for high school?
No. This topic stays at the grade 6-8 level: particle models, the periodic table, and simple balanced equations. It does not cover moles, stoichiometry calculations or electron configuration, which come later.
My child can name the parts of an atom but can't explain reactions. Where's the gap?
Usually it's the jump from labelling a diagram to tracking atoms through a change. Sessions target that by having the student count atoms before and after a reaction and account for every one.
Can chemistry be taught without a lab or experiments?
Reactions are discussed using demonstrations the student may have seen in class plus household examples like vinegar and baking soda. The focus here is on explaining and predicting what happens at the particle level, not on carrying out practicals.
How does the tutor handle chemical formulas over voice?
Formulas and equations are shown on screen as they are discussed, and the tutor reads them element by element with subscripts stated separately, so the student hears and sees the same thing.
Will this help with a science fair project or class test?
Sessions can be pointed at whatever unit the class is on - states of matter, the periodic table, or reactions - and the student can bring a worksheet or study guide to work through.

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