Answer: A scientific model is a physical and mathematical and conceptual representation of a system of ideas, events or processes.
ANd also for your second question i dont know what you mean?
Explanation:
Answer:
It is required 0.3 molecules of O2 to produce 0.6 molecules of H2O
Explanation:
The water´s formation reaction is: 2H2 + O2 --> 2H2O
This reaction shows the molecular O2:H2O ratio: 1:2.
Then, if we want to know how many molecules of O2 are required to produce 0.6 of H20, it is necessary calculate as it showed next:
0.6 molecules H2O * (1 molecula O2 / 2 molecules H2O)= 0.3 molecule O2
Answer
The molarity (M) of the H3PO4 solution = 1.0 M
Explanation
Given:
Mass of H3PO4 = 49.0 grams
Volume of the solution = 500 mL = 500/1000 = 0.5 L
What to find:
The molarity (M) of the H3PO4 solution.
Step-by-step solution:
Step 1: Convert 49.0 grams H3PO4 to moles using the mole formula.

The molar mass of H3PO4 = 97.994 g/mol
So,

Step 2: Calculate the molarity of the solution using the molarity formula.

Putting mole = 0.50 mol and volume = 0.50L into the formula, we have;

The molarity (M) of the H3PO4 solution = 1.0 M