Answer: 15.0 moles of
are formed from 30.0 mol of 
Explanation:
The balanced chemical reaction is :
According to stoichiometry :
2 moles of
give = 1 mole of 
Thus 30.0 moles of
will give =
of 
Thus 15.0 moles of
are formed from 30.0 mol of 
More dissolved oxygen is present in water with a lower temperature compared to water with a higher temperature. The reason for this inverse relationship between dissolved oxygen and temperature is that the solubility of a gas in a liquid is an equilibrium phenomenon.
Following the key in the diagram (see the attached image), the only particle diagram that represents a mixture of three substances is diagram 2.
To simplify it, let us replace the key in the diagram as follows;
- atom of one element = A
- atom of different element = B
Diagram 1 consists of only AA and AB
Diagram 2 consists of AA, BB, and AB.
Diagram 3 consists of AA and ABA
Diagram 4 consists of AA and BAB
Thus, only diagram 2 has a mixture of 3 substances.
More on mixtures can be found here: brainly.com/question/6594631
Magnesium dichloride or Magnesium chloride
Explanation:
2H2(g) + O2(g) → 2H2O(l )