Every card in Atoms, elements and compounds, Year 8: more practice
The whole deck, in order — so you can read it through before your child ever sees it.
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- A molecule of sulfuric acid has the formula H2SO4. Which elements does it contain?
Hydrogen, sulfur and oxygen
HintMatch each capital letter to an element.
WhyH is hydrogen, S is sulfur and O is oxygen. The small number 2 tells you there are two hydrogen atoms.
- In the formula CO, no number is written after either letter. How many atoms of each element does it show?
One carbon atom and one oxygen atom
HintA missing number never means none.
WhyIf no number follows a symbol, there is just one atom of that element. CO is carbon monoxide.
- Sodium reacts with chlorine. Name the compound formed (two words).
Sodium chloride
HintThe name of the metal comes first, then the non-metal with its ending changed.
WhyTwo elements join, so the name of the second one ends in -ide: chlorine becomes chloride.
- A compound is called potassium sulfate. Which elements does it contain?
Potassium, sulfur and oxygen
HintThe ending -ate tells you about an extra element.
WhyNames ending in -ate hide oxygen. Potassium sulfate is made of potassium, sulfur and oxygen.
- Three of these compounds contain only two elements. Which one contains three: sodium chloride, magnesium oxide, copper sulfate, potassium bromide?
Copper sulfate
HintCompare the endings of the four names.
WhyThe others end in -ide and each has just two elements. Copper sulfate contains copper, sulfur and oxygen, which is why its name ends in -ate.
- Zinc and sulfur are heated together and form zinc sulfide. How many different elements does it contain? (number only)
2
HintAn -ide ending tells you how many elements there are.
WhyThe ending -ide means a compound of just two elements. Here they are zinc and sulfur.
- How many atoms are there in total in 3H2O? (number only)
9
HintThe 3 in front multiplies the whole of H2O.
WhyOne H2O has two hydrogen atoms and one oxygen atom, which is 3 atoms. Three of them make 3 × 3 = 9.
- A particle diagram shows a box full of identical single circles, all separate from each other. Is it an element, a compound or a mixture?
An element
HintCount how many different kinds of circle there are.
WhyOnly one type of particle is present, so it is a single element. A compound would show different circles joined together.
- A diagram shows two different kinds of circle scattered about the box, none of them joined to the other kind. Is it an element, a compound or a mixture?
A mixture
HintLook for any joins between the different circles.
WhyTwo substances are present but not chemically bonded, so it is a mixture of two elements.
- In the word 'polymer', what does the prefix 'poly-' mean?
Many
HintThink of the word 'polygon'.
WhyA polymer is made of many repeating small units joined in a long chain. Poly- is also in polygon and polythene.
1★ KS3-CHEM-ATO-0037
2★ KS3-CHEM-ATO-0038
3★ KS3-CHEM-ATO-0039
4★ KS3-CHEM-ATO-0040
5★ KS3-CHEM-ATO-0041
6★ KS3-CHEM-ATO-0042
7★ KS3-CHEM-ATO-0043
8★ KS3-CHEM-ATO-0044
9★ KS3-CHEM-ATO-0045
10★ KS3-CHEM-ATO-0046
Keep what you learn
Here, nothing is saved. In your child’s own sky every card is scheduled — it comes back just before they’d forget it — and the professor who wrote it is one tap away.