Within a physical change, an element can change forms, such as going from solid to a liquid through melting. Color change can also occur during a physical change. Physical changes are very different from chemical changes. In a chemical change the element itself changes into something else within a reaction, such as combustion (burning).
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Answer:
1.7 * 10^-5
Explanation:
1- get the number of moles of PbCl2:
number of moles = mass / molar mass
number of moles = 0.45 / 278.1 = 1.618 * 10^-3 moles
2- get the concentration of Pb2+:
molarity = number of moles of solute / volume of solution in liters
molarity = (1.618 * 10^-3) / (0.1) = 0.0162 M
3- getting concentration of Cl-:
<span>PbCl2(s) <==> Pb2+(aq) + 2Cl-(aq)
</span>We can note that:
For a certain amount of Pb2+ formed, twice this amount of Cl- is formed.
This means that:
for 0.0162 M of Pb2+, 2*0.0168 = 0.0324 M of Cl- is formed
4- getting Ksp:
Ksp = [Pb2+][Cl-]²
Ksp = (0.0162)*(0.0324)²
Ksp = 1.7 * 10^-5
Hope this helps :)
I think it’s 7.41 because you count up all the atoms and find out how many are x (the large grey ones) and you do 2/27 x 100 which gives you 7.41 :) (sorry if i counted wrong it’s kinda hard)
A fast-flowing river would most likely be to move the skaters glide around the rink b<span>y lifting it up and carrying it downstream. In a fast-flowing river, the pressure is strong, which makes it easier for sand-sized particles of sediments to be carried or transferred. Hope this answer helps.</span>