Answer:
the answer is d which is soap solution because it's a soap solution that can measure the degree of hardness of a water if the water forms with this soap solution then the water is hard but if the water forms foam with soap then it is soft
Answer:
I think S.T.E.M but i'm not 100% sure
Explanation:
Ans: Moles of Fe(OH)2 produced is 5.35 moles.
Given reaction:
Fe(s) + 2NiO(OH) (s) + 2H2O(l) → Fe(OH)2(s) + 2Ni(OH)2(aq)
Based on the reaction stoichiometry:
1 mole of Fe reacts with 2 moles of NiO(OH) to produce 1 mole of Fe(OH)2
It is given that there are:
5.35 moles of Fe
7.65 moles of NiO(OH)
Here the limiting reagent is Fe
Therefore, number of moles of Fe(OH)2 produced is 5.35 moles.
We can write the balanced equation for the synthesis reaction as
H2(g) + Cl2(g) → 2HCl(g)
We use the molar masses of hydrogen chloride gas HCl and hydrogen gas H2 to calculate for the mass of hydrogen gas H2 needed:
mass of H2 = 146.4 g HCl *(1 mol HCl / 36.46 g HCl) * (1 mol H2 / 2 mol HCl) *
(2.02 g H2 / 1 mol H2)
= 4.056 g H2
We also use the molar masses of hydrogen chloride gas HCl and chlorine gas CL2 to calculate for the mass of hydrogen gas H2:
mass of CL2 = 146.4 g HCl *(1 mol HCl / 36.46 g HCl) * (1 mol Cl2 / 2 mol HCl) *
(70.91 g Cl2 / 1 mol Cl2)
= 142.4 g Cl2
Therefore, we need 4.056 grams of hydrogen gas and 142.4 grams of chlorine gas to produce 146.4 grams of hydrogen chloride gas.
