I believe it’s the third option
Chemically combined to make a new pure substance
Answer:
On the placement of hydrogen and helium in the periodic system
H1=1
He2=2
Answer:
Mass = 255 g
Explanation:
Given data:
Number of moles of nitrogen = 7.5 mol
Mass of ammonia formed = ?
Solution:
Chemical equation:
3H₂ + N₂ → 2NH₃
Now we will compare the moles of nitrogen and ammonia.
N₂ : NH₃
1 : 2
7.5 : 2/1×7.5 = 15
Mass of ammonia:
Mass = number of moles × molar mass
Mass = 15 mol × 17 g/mol
Mass = 255 g
The answer is
D. Covalent bond
Hope this helps you have a great day.