Exothermic reactions release heat the surrounding. So Freezing?
Answer: A. Limestone rocks dissolving in water
Explanation:
B: This is a physical change; it changes an object physically rather than chemically. It does not change the composition of the concrete, only the shape.
C: This is also a physical change because the water is just dragging sand with it, but not actually changing the composition of it.
D: Similar to option B, this is an example of physical weathering because the ice only divides the rock into different parts but doesn't change the composition or complexity of it.
Hi,
The answer should be C.
Hope this helps, if you’d like further explanation please let me know.
a) 6 electrons - because atomic number is the same as the electron number
b) 4 - because 6-2=4
c) Covalent bonds - it needs 4 more electrons for a full outer shell.