Among the choices, the polyatomic ion is only the third choice, NH4+ where it is composed of nitrogen one atom of nitrogen and 4 atoms of hydrogen. Choice 2 is a monoatomic atom being composed only of calcium. Then, the first and fourth choices are not ions because they are not charged.
Answer:
Precipitation Reactions
They contain two aqueous reactants, one aqueous product, and one solid product. In this reaction, two soluble products, Pb(NO3)2 and KI, combine to form one soluble product, KNO3, and one insoluble product, PbI2. This is a precipitation reaction, and PbI2 is the precipitate.
It all depends what theory it is most are supported by really good evidence but they just don't have all the evidence so it can't be proven a fact at that time
I found a presentation of Food web of a pond that will greatly connect with the above problem. http://www.eduweb.com/portfolio/earthsystems/food/foodweb4.html
Normal setting:
Species Pop. size
Blue heron Medium
Perch Medium
Bass Medium
Minnows Medium
Inverts Medium
Algae Medium
If PERCH population size decreases,
Species Pop. sizeBlue heron LowPerch LowBass MediumMinnows HighInverts HighAlgae Low
As you can see, 4 other species are affected when the Perch population size decreased. Bass is not affected.
Answer:
101.50 g H₂O
Explanation:
The mole ratio of HNO₃ and H₂O is 6 : 2
Hence, 16.9 moles of HNO₃ will produce = 2/6×16.9 = 5.63 moles of H₂O
Also,
Mass = Moles × M.Mass
Mass = 5.63 mol × 18.02 g/mol
Mass = 101.50 g H₂O
