

ok, now press calculator. i dont have it now.
Answer:
8.4
Explanation:
-log(4.08x10^-9) = 8.4
- Hope that helped! Please let me know if you need further explanation.
Answer: Compound
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Copper 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: water 

Thus as it give that the red sample on being heated, a gas is released and a blue powder is left after the heating. Thus the given sample is a compound.
Explanation:
solution 1) homogeneous
2) do not scatter light
3) cannot be separated by filtration
Colloids 1) heterogeneous
2) scatter light
3) cannot be separated by filtration
suspension 1) heterogeneous
2) may either scatter light or be opaque
3) can be separated by filtration