Answer:
If it is pure, the substance is either an element or a compound. If a substance can be separated into its elements, it is a compound. If a substance is not chemically pure, it is either a heterogeneous mixture or a homogeneous mixture. If its composition is uniform throughout, it is a homogeneous mixture.
Answer:
Reasonable Second step- 
Explanation:
The given single step chemical reaction is as follows.

Suppose a two-step mechanism is proposed for this reaction,
The reaction occured in two steps they are as follows.


Answer: There are
moles
present in
particles.
Explanation:
According to the mole concept, 1 mole of a substance contains
particles.
Hence, number of moles present in
particles are calculated as follows.
No. of moles =
mol
=
mol
Thus, there are
moles
present in
particles.
Answer:copper iodide and potassium sulfate
Explanation: