Ionic bondingIB MYP Chemistry: Mind map

Exam questions on Ionic bonding

1. A teacher in Nairobi burns a strip of magnesium ribbon in air. It burns with a dazzling white flame and leaves a white powder of magnesium oxide, an ionic compound. Magnesium atoms have two electrons in their outer shell and oxygen atoms have six.
   Describe, in terms of electrons, how magnesium oxide forms from magnesium atoms and oxygen atoms.2 marks
2. A geologist in Chile examines a cube-shaped crystal of rock salt, which is sodium chloride. When she taps the crystal with a hammer it splits into smaller pieces that are also cube-shaped. Sodium chloride is an ionic compound.
   Explain why the crystal splits into smaller pieces that are also cube-shaped.2 marks
3. A student in Lisbon makes a saturated solution of sodium chloride. She pours some into a shallow dish on a warm windowsill and some into a shallow dish in a cool cupboard, then leaves the water to evaporate and compares the crystals that form. She predicts that the slower the water evaporates, the larger the crystals will be.
   Identify the independent variable, the dependent variable and one control variable in her investigation.3 marks