9 Ammonia is manufactured from nitrogen and hydrogen by the Haber process.
N2(g) + 3H2(g)2NH3(g)
What is the percentage yield when 60 kg of ammonia is produced from 60 kg of hydrogen?
A
5.9%
B
17.6%
с
35.3%
D
50.0%

B

17.6%

Explanation:

1. Percentage yield = (Actual yield/theoretical yield) x 100

2. You know actual yield of ammonia (60kg) so you need to work out theoretical yield.

3. mols of hydrogen = m/mr = 60,000/2 = 30,000 mols.

4. 3:2 ratio so (30,000/3) x 2 = 20,000 mols of Ammonia.

5. Therefore mass of ammonia = mr x mols = 20,000 x 17 = 340,000 grams

6. So percentage yield is (60,000/340,000) x 100 = 17.6

he uptake of drugs from the intestine is often strongly influenced by diffusion. for example, consider a water-insoluble steroid for treating inflammation that is solubilized in aggregates of detergent molecules, called micelles. these micelles, aggregates of 80 soap molecules, have a molecular weight of 24,000, a diameter of 2.6 nm, and a charge of -27. the positively charge ions (counterions) in this system are na".

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.