Which example best describes a double displacement reaction?

the ions of two ionic compounds switch places and a gas is formed.

a compound reacts with oxygen to release a lot of heat.

one compound breaks down into two different compounds.

two compounds combine to form one new compound.

Aforce of attraction/repulsion due to the spin of electrons what is this force?

Describe the chemical reaction based on the chemical equation below. also, explain whether the equation is balanced.

Electromagnets coils of wire paper clips picked up 10 3 15 6 20 9 25 12 ms. owens' class was studying magnets. ms. owens showed her students how to make an electromagnet using a nail, a d-cell battery, and plastic coated wire. the students wrapped the wire around the nail and then attached the ends to the battery. when they were finished, they tested their magnets by investigating how many paperclips their magnets could pick up. they also tested whether they could increase the strength of their electromagnets by using more coils of wire. they recorded the class average of their results in the data table seen here. ms. owens asked her students to graph their data in a line graph. how should the students label the x-axis on their line graph? a) size of battery b) number of paper clips c) number of coils of wire d) strength of electromagnet