Answer:
Explanation:
Cubic decimeter is the same unit as liter; so, mole per cubic decimeter is mole per liter, and that is the unit of concentration of molarity. Thus, what is asked is the molarity of the solution. This is how you find it.
1. <u>Take a basis</u>: 1 dm³ = 1 liter = 1,000 ml
2. <u>Calculate the mass of 1 lite</u>r (1,000 ml) of solution:
- density = mass / volume ⇒ mass = density × volume
Here, the density is given through the specific gravity
Scpecific gravity = density of acid / density of water
Take density of water as 1.00 g/ml.
- density of solution = 1.25 g/ml
- mass solution = 1.25 g/ml × 1,000 ml = 1,250 g
3. <u>Calculate the mass of solute</u> (pure acid)
- % m/m = (mass of solute / mass of solution) × 100
- 56 = mass of solute / 1,250 g × 100
- mass of solute = 56 × 1,250g / 100 = 700 g
4. <u>Calculate the number of moles of solute</u>:
- moles = mass in grams / molar mass = 700 g / 70 g/mol = 10 mol
5. <u>Calculate molarity (mol / dm³)</u>
- M = number of moles of solute / liter of solution = 10 mol / 1 liter = 10 mol/liter.
Answer:
B. Libra
Explanation:
Libra's range from September 23rd to October 22nd
Answer:
The answer to your question is V = 0.32 L
Explanation:
Data
Volume of NH₃ = ?
P = 3.2 atm
T = 23°C
mass of CaH₂ = 2.65 g
Balanced chemical reaction
6Ca + 2NH₃ ⇒ 3CaH₂ + Ca₃N₂
Process
1.- Convert the mass of CaH₂ to moles
-Calculate the molar mass of CaH₂
CaH₂ = 40 + 2 = 42 g
42 g ------------------ 1 mol
2.65 g -------------- x
x = (2.65 x 1)/42
x = 0.063 moles
2.- Calculate the moles of NH₃
2 moles of NH₃ --------------- 3 moles of CaH₂
x --------------- 0.063 moles
x = (0.063 x 2) / 3
x = 0.042 moles of NH₃
3.- Convert the °C to °K
Temperature = 23°C + 273
= 296°K
4.- Calculate the volume of NH₃
-Use the ideal gas law
PV = nRT
-Solve for V
V = nRT / P
-Substitution
V = (0.042)(0.082)(296) / 3.2
-Simplification
V = 1.019 / 3.2
-Result
V = 0.32 L
<span>The pH is given by the Henderson - Hasselbalch equation:
pH = pKa + log([A-]/[HA])
pH = -log(</span><span>1.3 x 10^-5) + log(0.50/0.40)
pH = 4.98
The answer to this question is 4.98.
</span>
I think it’s C atomic radius and numbers of unshielded protons
