Knowing the number of valence electrons in one of the alien elements helps in identifying it because the number of valence electrons can help categorize the alien element. Similar elements have the same valence electrons and knowing the category of the element can help further analyze the element.
To determine the pOH assuming water is the universal solvent take the value of 10 ^ -14 and then divide it by the hydronium concentration and then take the negative logarithm of the final answer that is the solution to the hydroxide ion concentration in the solution.
<span>(A)hydrochloric acid + silver nitrate
HCl(aq) + AgNO3(aq) -----> AgCl(s) +HNO3(aq)
</span><span>(B)hydrochloric acid + sodium hydroxide
</span><span>HCl(aq) + NaOH(aq) -----> NaCl(aq) + H2O(l)
</span><span>(C)calcium chloride + silver nitrate
CaCl2(aq) + AgNO3(aq) ----> </span>AgCl(s) +Ca(NO3)2(aq)
<span>(D)sodium chloride + silver nitrate
</span>NaCl(aq) + AgNO3(aq) ----> AgCl(s) +NaNO32(aq)
AgCl is a white precipitate.
In (B) no precipitate was formed, so answer is B.
First step is to get the mass of the mercury:
Pressure = mass/volume
mass = pressure x volume = 13.5 x 1.85 = 24.975 gm
Second step is to calculate the number of moles in 24.975 gm:
From the periodic table, the molar mass of mercury is 200.59
mass = number of moles x molar mass
number of moles = 24.975 / 200.59 = 0.1245 mole
Last step is to get the number of atoms:
Each mole contains 6.02 x 10^23 atoms
number of atoms = 0.1245 x 6.02 x 10^23 = 7.4949 x 10^22 atoms
So solve
this we must know the amount of sugar per gram of coffee
<span>i.
</span>10 g sugar /100 g coffee = 0.1 g sugar/ 1 g coffee
<span>ii.
</span>10 g sugar / 200 g coffee = 0.05 g sugar / 1 g coffee
<span>iii.
</span>4 g sugar / 200 g coffee = 0.02 g sugar / 1 g coffee
<span>iv.
</span>4 g sugar / 100 g coffee = 0.04 g sugar / 1 g coffee
So the ranking from sweetest so the least is:
<span> i, ii, iv, iii</span>