Q1)
We have been given the OH⁻ concentration, therefore we first need to find the pOH value and then the pH value.
pOH = -log [OH⁻]
pOH = -log (0.225 M)
pOH = 0.65
pH + pOH = 14
pH = 14 - 0.65 = 13.35
Q2)
pOH = -log[OH⁻]
pOH = -log (0.0015 M)
pOH = 2.82
pH + pOH = 14
pH = 14 - 2.82
pH = 11.18
<span>Use the sequence E (NaCl, Na2SO4, then Na2S). Silver is insoluble as a chloride, so it would be removed first, the others (Pb and Ni) are soluble as chlorides(Note; lead chloride is soluble as a hot solution but will ppt when cold), next, PbSO4 is insoluble but NiSO4 is soluble so use Na2SO4 to separate lead from nickel. Lastly, nickel sulfide is insoluble and can be separated and collected.
Hope I helped :)</span>
No, this item is not made of pure silver because if it has been made from pure silver that it would have displaced only 1.16cm³ of water but due to the addition of some other low-density element it displaces 1.9cm³ of water.
<u>For pure silver</u>
density of pure silver is = 10.49 g/cm³
mass of silver = 12.2 gram
since, density = mass/volume
volume = mass/density
= 12.2/10.49 cm³
= 1.16 cm³
But the actual displaced water is <u>1.9cm³</u>, which means some other element of lower density has been added.
Therefore, it is clear that the given jewelry is not made of pure silver.
Learn more about silver here:-brainly.com/question/17086277
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Answer:
3.56x10^24 molecules
Explanation:
The following data were obtained from the question:
Mass of Na2SO4 = 840g
Molar Mass of Na2SO4 = (23 x2) + 32 + (16x4) =46 + 12 + 64 = 142g/mol
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. This also gives that 1mole of Na2SO4 contains 6.02x10^23 molecules.
If 1 mole (i.e 142g) contains 6.02x10^23 molecules,
Therefore, 840g of Na2SO4 will contain = (840 x 6.02x10^23)/142 = 3.56x10^24 molecules
The equilibrium constant (Kp) for the formation of the air pollutant nitric oxide (NO) in an automobile engine at 530 degree C is 2.9 x 10 to the minus eleventh
N2(g) + O2 (g) = 2 NO (g)
