Answer:
The correct answer to this question is (c) 25.0 m
Explanation:
To solve this we list out the variables thus
mole fraction of sodium hydroxide = 0.310
Mole fraction = number of moles of a component ÷ total number of moles in the solution
Mole fraction = 0.310
In a saturaturated aqueous solution we have NaOH and water
∴ Number of moles of water molecules per unit = 1 - 0.310 = 0.690
However 0.690 moles of H₂O weighs = 0.690 mole × 18.01528 g/mol =12.43 g = 0.01243 kg of H₂O
But the molality = number of moles per Kilogram of H₂O
therefore molality of NaOH in the sample of solution =
(0.310 mol of NaOH )÷(0.01243 kg of H₂O)
= 24.93 mol/kg or ≅ 25.0 m
Im pretty positive its A , hope this helps!
Answer:
I think is the last one.
Anthracite – Stage Four
Anthracite, the fourth stage in coal formation, is also known as “hard coal” because it is hard and has a high lustre. It appears to have been formed as a result of combined pressure and high temperature. Anthracite burns with a short flame and little smoke.
Manganese alone cannot be a catalyst. However, its oxides can work as a catalyst. Manganes (II, III) oxide has found some applications in certain reactions as a catalyst. These reactions are the oxidation of methane, carbon monoxide, decomposition of NO and the catalytic combustion of organic compounds.
Answer: C. Adding concentrated HCL(aq)
Explanation:
HCl is an efficient acid that will increase the quantity of H+ in the solution and thus reduce the ionizing percentage of Ch3CO2H. The amount of ionization of the latter would be reduced by the addition of strong acid to a solution of weak acid.