Answer:
The 3rd one is correct
Explanation:
Protons and neutrons have approximately the same mass, about 1.67 × 10−24 grams, which scientists define as one atomic mass unit (amu) or one Dalton. Each electron has a negative charge (−1) equal to the positive charge of a proton (+1). Neutrons are uncharged particles found within the nucleus.
<span>Co3+ is Cobalt with three electrons removed (It's positive by 3). So, the abbreviated notation for Cobalt, minus three electrons (Coming from 4s and 3d) is:
[Ar]4s1, 3d5</span>
A reaction in which Oxygen (O₂) is produced from Mercury Oxide (HgO) would be a decomposition reaction.
2HgO → 2Hg + O₂
If 250g of O₂ is needed to be produced,
then the moles of oxygen needed to be produced = 250g ÷ 32 g/mol
= 7.8125 mol
Now, the mole ratio of Oxygen to Mercury Oxide is 1 : 2
∴ if the moles of oxygen = 7.8125 mol
then the moles of mercury oxide = 7.8125 mol × 2
= 15.625 mol
Thus the number moles of HgO needed to produce 250.0 g of O₂ is 15.625 mol
Answer:
E) HBr
Explanation:
Because Bromine (Br) isn't part of the original formula for Apirin. (I answered this based on the assumption that the letter "A" in option C was a typo of sorts, since there is no element with a chemical symbol of just "A" that I am aware of. If this is incorrect, then I apologize.)