In what ways lithium shows similarities to magnesium in its chemical behaviour?

What is meant by 'diagonal relationship'? Why do some elements show diagonal relationship? How does lithium resemble magnesium in its chemical behaviour?

In what ways does boron show similarities to silicon which is diagonally opposite to it in the periodic table ?

Which gas shows real behaviour?

Fungi and algae show similarity in

Name two elements you would expect to show chemical reactions similar to magnesium. What is the basis for your choice?

Archaebacteria shows similarity with Mycoplasma in having :

hCG is similar in its actions to

Under what conditions to gases show maximum deviations from ideal gas behaviour ?

The chemistry of lithium is very similar to that to that of magnesium even though they are placed in different groups. Its reason is

Explain why the elements of the same group exhibit the same chemical behaviour.