<h3><u>Answer;</u></h3>
pOH = 3.08
<h3><u>Explanation;</u></h3>
NX3 + H2O <----> NHX3+ + OH-
Kb = 4.0 x 10^-6
Kb = c(NH₄⁺) · c(OH⁻) ÷ c(NH₃).
c(NH₄⁺) = c(OH⁻) = x.
x² = Kb · c(NH₃)
x² = 4.0 × 10⁻⁶ × 0.175 = 7.0 × 10⁻⁷.
x = c(OH⁻) = √(7.0 × 10⁻⁷)
= 8.367 × 10⁻⁴
pOH = -log(c(OH⁻))
=- log ( 8.367 × 10⁻⁴)
<u>= 3.08</u>
Answer:
1. 7.256g of NaCl
2. 47.33g of Cl2
Explanation:
2 moles of Na reacts to produce 2 moles of NaCl
8 moles of Na will still produce 8 moles of NaCl
Mass of NaCl = molar mass of Nacl/moles of Nacl
=58.5/8
=7.256g of NaCl
From the equation, 2 moles of Na reacts with 1 mole of Cl2
3/2 moles of Cl2 will react with 3 moles of Na
Mass of Cl2 = 71/1.5
=47.33g of Cl2
The heart is a part of the Circulatory system.
Answer:
15.4 g of sucrose
Explanation:
Formula to be applied for solving these question: colligative property of freezing point depression. → ΔT = Kf . m
ΔT = Freezing T° of pure solvent - Freezing T° of solution
Let's replace data given: 0°C - (-0.56°C) = 1.86 C/m . m
0.56°C / 1.86 m/°C = m → 0.301 mol/kg
m → molality (moles of solute in 1kg of solvent)
Our mass of solvent is not 1kg, it is 150 g. Let's convert it from g to kg, to determine the moles of solute: 150 g. 1kg/1000g = 0.150 kg
0.301 mol/kg . 0.150kg = 0.045 moles.
We determine the mass of sucrose, by the molar mass:
0.045 mol . 342 g/1mol = 15.4 g
Answer:
= 1.271 J/g°C
Explanation:
Heat released by the metal sample will be equivalent to the heat absorbed by water.
But heat = mass × specific heat capacity × temperature change
Thus;
Heat released by the solid;
= 225 g × c ×(67 -53) , where c is the specific heat capacity of the metal
= 3150 c joules
Heat absorbed by water;
= 25.6 g × 4.18 J/g°C × (53-15.6)
= 4002.0992 joules
Therefore;
3150 c joules = 4002.0992 joules
c =4002.0992/3150
<u> = 1.271 J/g°C</u>
