<u>Analysing the Question:</u>
We are given a 250 mL solution of 0.5M K₂Cr₂O₇
Which means that we have:
0.5 Mole in 1L of the solution
0.125 moles in 250 mL of the solution <em>[dividing both the numbers by 4]</em>
<em />
<u>Mass of K₂Cr₂O₇ in the given solution:</u>
Molar mass of K₂Cr₂O₇(Potassium Dichromate) = 194 g/mol
<em>we know that we have 0.125 moles in the 250 mL solution provided</em>
Mass = Number of moles * Molar mass
Mass = 0.125 * 194
Mass = 36.75 grams
Nothing unless it was dug out from roots if not they would grom back in a long period of time
Answer:
The metal cube lattice is made of only one kind of atom.
Explanation:
As we know that metallic crystals are made up of only one kind of element. A metal crystal is actually a huge sea of positive charges embedded in the layers of negative charges (electrons). The whole crystal is made up of same kind of atoms, e.g crystals of gold, crystals of iron.
If we talk about structure of metallic crystal, it can be body centered cubic, simple cubic, hexagonal or close cubic packing.
Now, coming towards the ionic crystals, we know that they are basically the crystals of ionic compounds like sodium chloride or cesium chloride. These crystals are formed due to ionic bonding between two or more than two kinds of elements/atoms. It is not possible for an ionic crystal to be composed of only one kind of atom. As far as structure is concerned, they can have different structure based on bonding between atoms in an ionic compound, e.g NaCl has octahedral geometry.
Therefore, it is very evident that best option is A.
Hey there!
Mass = 5.6 Kg
Volume =8.2 L
D = m / V
D = 5.6 / 8.2
D = 0.6829 Kg/L
hope this helps!
Answer:
(a) 
(b) 
(c) 
(d) 
Explanation:
Hello,
In this case, given the solubility of each salt, we can compute their molar solubilities by using the molar masses. Afterwards, by using the mole ratio between ions, we can compute the concentration of each dissolved and therefore the solubility product:
(a) 
In such a way, as barium and selenate ions are in 1:1 molar ratio, they have the same concentration, for which the solubility product turns out:
![Ksp=[Ba^{2+}][SeO_4^{2-}]=(6.7x10^{-4}\frac{mol}{L} )^2\\\\Ksp=4.50x10^{-7}](https://tex.z-dn.net/?f=Ksp%3D%5BBa%5E%7B2%2B%7D%5D%5BSeO_4%5E%7B2-%7D%5D%3D%286.7x10%5E%7B-4%7D%5Cfrac%7Bmol%7D%7BL%7D%20%20%20%29%5E2%5C%5C%5C%5CKsp%3D4.50x10%5E%7B-7%7D)
(B) 
In such a way, as barium and bromate ions are in 1:2 molar ratio, bromate ions have twice the concentration of barium ions, for which the solubility product turns out:
![Ksp=[Ba^{2+}][BrO_3^-]^2=(7.30x10^{-3}\frac{mol}{L})(3.65x10^{-3}\frac{mol}{L})^2\\\\Ksp=1.55x10^{-6}](https://tex.z-dn.net/?f=Ksp%3D%5BBa%5E%7B2%2B%7D%5D%5BBrO_3%5E-%5D%5E2%3D%287.30x10%5E%7B-3%7D%5Cfrac%7Bmol%7D%7BL%7D%29%283.65x10%5E%7B-3%7D%5Cfrac%7Bmol%7D%7BL%7D%29%5E2%5C%5C%5C%5CKsp%3D1.55x10%5E%7B-6%7D)
(C) 
In such a way, as ammonium, magnesium and arsenate ions are in 1:1:1 molar ratio, they have the same concentrations, for which the solubility product turns out:
![Ksp=[NH_4^+][Mg^{2+}][AsO_4^{3-}]^2=(1.31x10^{-4}\frac{mol}{L})^3\\\\Ksp=2.27x10^{-12}](https://tex.z-dn.net/?f=Ksp%3D%5BNH_4%5E%2B%5D%5BMg%5E%7B2%2B%7D%5D%5BAsO_4%5E%7B3-%7D%5D%5E2%3D%281.31x10%5E%7B-4%7D%5Cfrac%7Bmol%7D%7BL%7D%29%5E3%5C%5C%5C%5CKsp%3D2.27x10%5E%7B-12%7D)
(D) 
In such a way, as the involved ions are in 2:3 molar ratio, La ion is twice the molar solubility and MoOs ion is three times it, for which the solubility product turns out:
![Ksp=[La^{3+}]^2[MoOs^{-2}]^3=(2*1.58x10^{-5}\frac{mol}{L})^2(3*1.58x10^{-5}\frac{mol}{L})^3\\\\Ksp=1.05x10^{-22}](https://tex.z-dn.net/?f=Ksp%3D%5BLa%5E%7B3%2B%7D%5D%5E2%5BMoOs%5E%7B-2%7D%5D%5E3%3D%282%2A1.58x10%5E%7B-5%7D%5Cfrac%7Bmol%7D%7BL%7D%29%5E2%283%2A1.58x10%5E%7B-5%7D%5Cfrac%7Bmol%7D%7BL%7D%29%5E3%5C%5C%5C%5CKsp%3D1.05x10%5E%7B-22%7D)
Best regards.
