Answer:
11. A)outward
12. B) inward
13. B) opaque
14. I really don't know (sorry)
Explanation:
Answer:

Explanation:
In a single-displacement reaction, one element exchanges partners with another element in a compound.

This is a single-displacement reaction, because the element Fe exchanges partners with H in HCl.

This is not a single-displacement reaction, because it is a reaction between two compounds.
This is a double displacement reaction in which the K⁺ and H⁺ cations change partners with the anions.

This is not a single-displacement reaction. It is another double displacement reaction, in which the Na⁺ and H⁺ cations change partners with the anions.

This is a single-displacement reaction, because the element Ca exchanges partners with H in H₂O.
are not single-displacement reactions.
That's false. Because, the molecules in a solid are compacted too tightly together that they don't have all that extra space that a gas would. Molecules in a gas would have more thermal energy because they have all that space to move around in. The more they move around, the hotter it gets. The less that they move around, and the more that they put and packed together, the colder it's going to be.
Hope this helped you!! (: