There are several various of expressing concentration. For instance, mass percent, volume percent, Molarity, Normality, Molality, etc.
In present case, weight of solute and solvent are given, so it will be convenient to express concentration in terms of mass percent.
Given: weight of solute (Ca2+) = 8500 g
weight of solvent (water) = 490 g.
Therefore, mass of solution = 8500 + 490 = 8990 g
Now, mass percent =

=

= 94.55 %
Answer: Concentration of calcium ions is in this solution is 94.55 % (w/W)
Answer:Physical
Explanation:
State Change is physical because it changes without it being chemically done. So when water changes from a liquid to a solid the state of it is changing. (Solid or Liquid or Gas)
Basically what is physically being changed with out a chemical.
Mass of CO₂ = 132 g
<h3>Further explanation
</h3>
A mole is a number of particles(atoms, molecules, ions) in a substance
This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles
Can be formulated :
N = n x No
N = number of particles
n = mol
No = 6.02.10²³ = Avogadro's number
mole also can be formulated :

moles of CO₂ = 3
mass of CO₂(MW=44.01 g/mol) :

Answer:
I think the answer is B or Compounds
Recycling Isn’t Always Cost Effective.
High Up Front Cost
Needs More Global Buy-In.
Recycled Products Are Often of Lesser Quality.
Recycling Sites Are Commonly Unsafe.