I believe the third one if i am not mistaken
Answer:
a) 7.0 moles of NH3
b) 61.2 g of NH3
c) 4.15 g of H2
d) 8.9 ×10^19 molecules
Explanation:
Equation of the reaction;
N2(g) + 3H2(g) ⇄NH3(g)
a)
If 3 moles of H2 yields 1 mole of NH3
21 moles of H2 will yield 21 × 1 /3 = 7.0 moles of NH3
b)
1 mole of N2 yields 17 g of NH3
3.6 moles of N2 yields 3.6 moles × 17 g of NH3 = 61.2 g of NH3
c)
If 6g of H2 produces 17 g of NH3
xg of H2 will produce 11.76 g of NH3
x= 6 × 11.76/17
x= 4.15 g of H2
d)
If 6g of hydrogen yields 6.02 × 10^23 molecules of NH3
8.86 × 10^-4g of H2 yields 8.86 × 10^-4g × 6.02 × 10^23 /6 = 8.9 ×10^19 molecules
Answer:
84.75°C is the boiling point of water at an elevation of 7000 meter.
Explanation:
Rate of change of pressure = 19.8 mmHg/1000 ft
1 foot =
meter

Pressure change for every 1 m = 0.065 mmHg × 1= 0.065 mmHg
Elevation Pressure
0 m 760 mmHg
1000 m 695 mmHg
2000 m 630 mmHg
Pressure drop at the elevation of 7000 m: 
Pressure at 7000 m = 760 mmHg - 455mmHg = 305 mmHg
The boiling point of water decreases 0.05°C for every 1 mmHg drop in atmospheric pressure.
At 7000 meter elevation the boiling of water will be :

Boiling point of water at 7000 meter elevation :

84.75°C is the boiling point of water at an elevation of 7000 meter.
The answer is it tends to be more negative down a group. This is because as you go down the periodic table, the elements have more electron shells in their atoms. This makes the outermost shells less attracted to the nucleus due to their greater distances from the nucleus. Therefore, these shells are less likely to attract electrons (hence lower electron affinity) and are even more likely to lose electrons from their outer electron orbits.
Nucleotides are organic molecules consisting of a nucleoside and a phosphate.
They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver.
Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine.
Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular functions that demand energy, including: amino acid, protein and cell membrane synthesis, moving the cell and cell parts (both internally and intercellularly), cell division, etc.
Learn more about nucleoside at:
brainly.com/question/28482667
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