"Lead" in lead pencil is:
Correct answer: B. Graphite and clay
- A. Bone black
- B. Graphite and clay
- C. Lead oxide
- D. Lead peroxide
Explanation
The pencil "lead" is actually a mixture of graphite and clay. More clay in the mixture makes the lead harder. A harder lead has a higher number. Pencils are numbered from 1-3 but most people use a number 2.
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About s-Block and p-Block Elements
The s and p blocks are studied through their valence-shell configurations, periodic trends and characteristic chemical properties. Work covers the reactions of Group I and Group II elements, the behaviour of Group IV elements, and how atomic size, ionization energy, electronegativity and metallic character change across periods and down groups.
Practise s-Block and p-Block Elements
1,359 free s-Block and p-Block Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
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