Document page
chemistry igcse acapprinted 56 · PDF 56
145 pagesrevision 46934
printed 56 · PDF 56
Page image rendered from the stored file at 110 dpi; it sharpens as you zoom. Outlines are placed from each region’s stored position on the page (612 × 792 pt).
readable
Source of this text: embedded text layer. The better of the embedded text and OCR is kept.
56
A) It involves a transfer of electrons.
B) It consists of a lattice of positive ions.
C) It involves shared pairs of electrons.
D) It has ionic bonds between hydrogen and carbon.
Answer: C) It involves shared pairs of electrons.
5. Which statement explains why graphite conducts electricity?
A) It has a giant ionic structure.
B) It contains free-moving electrons between its layers.
C) It has delocalized protons in its structure.
D) It has covalent bonds that allow electron movement.
Answer: B) It contains free-moving electrons between its layers.
P4 :
Describe the type of bonding that occurs in metals and explain why metals are good
conductors of electricity.
Explain why ionic compounds tend to have high melting points.
Describe how a covalent bond is formed between two atoms of hydrogen.
Explain why graphite can conduct electricity but diamond cannot, even though both are
forms of carbon.
Why do substances with simple molecular structures, such as chlorine (Cl₂), tend to have
low boiling points compared to substances with giant covalent structures like silicon
dioxide (SiO₂)?