EASY
Lower Secondary Stage 9
IMPORTANT
Earn 100
Write the word equation for the reaction of potassium with water.
Important Questions on The Periodic Table
MEDIUM
Lower Secondary Stage 9
IMPORTANT
When elements react with other elements their atoms form a full outer shell of electrons. Use this information to suggest why the noble gases are unreactive.
MEDIUM
Lower Secondary Stage 9
IMPORTANT
Rubidium is the fourth element in Group 1. Predict what you would observe when rubidium is added to some water. Give a reason for your answer.
MEDIUM
Lower Secondary Stage 9
IMPORTANT
Describe the trend in the melting points and boiling points of the Group 1 elements.
MEDIUM
Lower Secondary Stage 9
IMPORTANT
Caesium is in Period 6 in Group 1. Would you expect caesium to have a higher or lower melting point than rubidium? Give a reason for your answer.
EASY
Lower Secondary Stage 9
IMPORTANT
Write the word equation for the reaction between hydrogen and chlorine.
MEDIUM
Lower Secondary Stage 9
IMPORTANT
Astatine is the element below iodine in group 7. Would you expect astatine to be more or less reactive than iodine? Give a reason for your answer.
MEDIUM
Lower Secondary Stage 9
IMPORTANT
Why did Mendeleev's periodic table contain fewer elements than the one we use today?
HARD
Lower Secondary Stage 9
IMPORTANT
Answer the following questions:
a) What question was Mendeleev trying to answer?
b) What evidence did he use?
c) How did Mendeleev think creatively?
d) What new evidence supported Mendeleev's ideas?
