Answer:
Molar mass→ 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Explanation:
Let's apply the formula for freezing point depression:
ΔT = Kf . m
ΔT = 74.2°C - 73.4°C → 0.8°C
Difference between the freezing T° of pure solvent and freezing T° of solution
Kf = Cryoscopic constant → 5.5°C/m
So, if we replace in the formula
ΔT = Kf . m → ΔT / Kf = m
0.8°C / 5.5 m/°C = m → 0.0516 mol/kg
These are the moles in 1 kg of solvent so let's find out the moles in our mass of solvent which is 0.125 kg
0.0516 mol/kg . 0.125 kg = 6.45×10⁻³ moles. Now we can determine the molar mass:
Molar mass (mol/kg) → 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
The answer would be B.
U-238 has a n to p ration of 1.6:1. 146 neutrons and 92 protons.
It is actually the most commonly used isotope is reactors.
C-14 is also a radioactive isotope with 8 neutrons and 6 protons.
The usual and ideal n to p ratio is 1:1 such as C-12 or Mg-24
Answer:
False- The number of electrons does not affect the type of element.
Explanation:
The adding/removing of protons is what changes the type of element. for example, if you have a molecule of Boron, which has 5 protons, and you add one proton, you will have created a carbon molecule with 6 protons. The number of protons of an element is its atomic number. Elements can have varying numbers of both electrons and neutrons without changing the type of element.
A burning splint will burn more vigorously in pure oxygen than in air because <span>oxygen is a reactant in combustion and concentration of oxygen is higher in pure oxygen than is in air.
Oxygen concentration in air is approximately 20%, the rest of are nitrogen, carbon dioxide and other gases. Oxygen is oxidazing reactant, that means oxygen give electrons in chemical reactions.
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