Answer:- 14.9 M
Solution:- Given commercial sample of ammonia is 28% by mass. Let's say we have 100 grams of the sample. Then mass of ammonia would be 28 grams.
Density of the solution is given as 0.90 grams per mL.
From the mass and density we could calculate the volume of the solution as:

= 111 mL
Let's convert the volume from mL to L as molarity is moles of solute per liter of solution.
= 0.111 L
Now, we convert grams of ammonia to moles on dividing the grams by molar mass. Molar mass of ammonia is 17 gram per mole.

= 1.65 mole
To calculate the molarity we divide the moles of ammonia by the liters of solution:

= 14.9 M
So, the molarity of the given commercial sample of ammonia is 14.9 M.
Answer:
Shield Volcano . I've been their before
Explanation:
Answer:
D
Explanation:
Because do all of that and then you do a conclusion
3.01 Ă— 10^24 Ă— (12/5) hydrogen atoms
Looking at the formula for the molecule, the ratio of carbon to hydrogen atoms is 5:12, so if we divide the number of carbon atoms by 5 and then multiply by 12, we can find the number of hydrogen atoms. Let's look at the available options and see what makes sense.
3.01 Ă— 10^24 Ă— (12/5) hydrogen atoms
* This is exactly correct.
(3.01 Ă— 10^24 / 5) hydrogen atoms
* Nope. This will tell you how many pentane MOLECULES you have, but not the number of hydrogen atoms.
3.01 Ă— 10^24 Ă— (5/12) hydrogen atoms
* Close, but the ratio (5/12) will tell you the number of carbon atoms you have if you give it the number of hydrogen atoms. So this choice is wrong.
3.01 Ă— 10^24 Ă— 12 hydrogen atoms description
* This would tell you the number of hydrogen atoms you have if you know the number of pentane molecules you have. So this choice is also wrong.