Answer: single replacement reaction, 
Explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution.
A general single displacement reaction can be represented as :

As strontium metal is added to aluminum chlorate , strontium being more reactive than aluminium, displaces aluminium atom its salt solution and lead to formation of strontium chlorate and aluminum metal.

Answer:
Electrons are transferred between atoms together in the ionic compound. The ions are arranged in a regular repeating pattern in an ionic crystal
Explanation:
"The other halogens are not as electronegative and so other hydrogen halides cannot form hydrogen bonds between molecules. Only London Forces are formed. - Therefore more energy is required to break the intermolecular forces in HF than the other hydrogen halides and so it has a higher boiling point."
not a hack link, just stating where i got your answer from! -
https://www.mytutor.co.uk/answers/17558/A-Level/Chemistry/Explain-the-unusually-high-boiling-point-of-HF/