Concentration can be expressed in different forms: molarity, molality, normality, percentage, part per million and many more. For molality, it is a unit of concentration expressed as moles of solute per kilogram of solvent. Therefore,
0.3 = moles solute/0.10 kg solvent
moles solute = 0.03 moles
Answer:
2.4 × 10⁻⁴ M
Explanation:
Step 1: Calculate the concentration of Mg²⁺ coming from Mg(NO₃)₂
Mg(NO₃)₂ is a strong electrolyte and the molar ratio of Mg(NO₃)₂ to Mg²⁺ is 1:1. The initial molar concentration of Mg²⁺ is 1/1 × 0.36 M = 0.36 M.
Step 2: Make an ICE chart for the solution of MgF₂
MgF₂(s) ⇄ Mg²⁺(aq) + 2 F⁻(aq)
I 0.36 0
C +S +2S
E 0.36+S 2S
The solubility product constant is:
Ksp = [Mg²⁺] × [F⁻]² = (0.36+S) × (2S)²
Since S <<< 0.36, 0.36+S ≈ 0.36.
Ksp = 0.36 × 4S² = 8.4 × 10⁻⁸
S = 2.4 × 10⁻⁴ M
Answer:
Because there is trapped air inside the cube of ice
Explanation:
when water freezes it has water molecules and air molecules and as it freezes they move slower and slower until it freezes and they become stuck
The steps to be followed while cleaning volumetric glassware are:
1. Remnants from the previous measurements are wiped off with the help of paper towel.
2. The glassware is then soaked overnight in warm soap solution.
3. Then before rinsing with tap water, the glassware are scrubbed with an appropriate brush.
4. After scrubbing, the glassware is rinsed thoroughly with tap water in order to make sure there are no traces of soap solution.
5. The glassware is then rinsed with de-ionized water and finally with the solution that would be used for the volumetric measurement.
Answer:
The answer is: 11759 Hz
Explanation:
Given: Chemical shift: δ = 211.5 ppm, Spectrometer frequency = 556 MHz = 556 × 10⁶ Hz
In NMR spectroscopy, the chemical shift (δ), expressed in ppm, of a given nucleus is given by the equation:



<u>Therefore, the signal is at 11759 Hz from the TMS.</u>