What is the relationship between the melting point and freezing point of a substance?
If water melts at 0°C, at what temperature does it freeze?
Explain why the melting and freezing points of a substance are the same.
At what temperature does iron freeze if its melting point is 1538°C?
Describe what happens to particles at the freezing point of a substance.
What happens to the reactivity of halogens as you move down Group 7?
Why does the reactivity of halogens decrease as you go down the group?
Which halogen is the most reactive: fluorine, chlorine, or iodine?
Predict what would happen if chlorine was added to a solution of potassium iodide.
What did Mendeleev do when elements didn’t seem to fit in his periodic table?
Why did Mendeleev leave gaps in his periodic table?
What did Mendeleev predict about the elements that would fill the gaps in his periodic table?
Why were Mendeleev’s predictions important for his acceptance by other scientists?
What event led to Mendeleev being credited by scientists for his periodic table?