Answer:
0.33 mol/kg NH₃
Explanation:
Data:
b(NH₃) = 0.33 mol/kg
b(Na₂SO₄) = 0.10 mol/ kg
Calculations:
The formula for the boiling point elevation ΔTb is
i is the van’t Hoff factor — the number of moles of particles you get from a solute.
(a) For NH₃,
The ammonia is a weak electrolyte, so it exists almost entirely as molecules in solution.
1 mol NH₃ ⟶ 1 mol particles
i ≈ 1, and ib = 1 × 0.33 = 0.33 mol particles per kilogram of water
(b) For Na₂SO₄,
Na₂SO₄(aq) ⟶ 2Na⁺(aq) + 2SO₄²⁻(aq)
1 mol Na₂SO₄ ⟶ 3 mol particles
i = 1 and ib = 3 × 0.10 = 0.30 mol particles per kilogram of water
The NH₃ has more moles of particles, so it has the higher boiling point.
Answer:
Explanation:
Then, multiply the number of moles of Na by the conversion factor 6.02214179×1023 atoms Na/ 1 mol Na, with 6.02214179×1023 atoms being the number of atoms in one mole of Na (Avogadro's constant), which then allows the cancelation of moles, leaving the number of atoms of Na.Aug 15, 2020
Answer:
Cl2
Explanation:
Cl2 is a covalent molecule because it contains 2 non-metal elements.
It is non-polar because both elements have the same level of electrostatic attraction (remember that electrostatic attraction is the tendency to steel an electron from an element with lower a lower electrostatic force)
In Cl2 since there are only 2 molecules that are the exact same there is no overall dipole (which means that one end of the molecule is slightly positive or negative charge)
If the molecule replaced one Cl or something else then it would be non-polar since one element will be more electrostatic than the other and one region of the molecule will have a slightly positive or negative charge, unless the molecule is symmetrical like CH4.
For CH4 (methane) if you drew this as a lewis structure the Carbon would be surrounded by 4 hydrogen atoms meaning the overall dipole will be cancelled out since the molecule is symmetrical.
You may not understand the last part but just know that:
If there are 2 of the same atoms in the molecule (Cl2) then it is non-polar
If there are 2 non-metals then the bond is covalent
Water is always polar
Answer : The approximate atomic mass of an oxygen atom daltons (Da) is, 16 Da
Explanation :
As we know that dalton (Da) is equal to atomic mass unit (amu).
As we are given that,
Element = oxygen
Atomic number of oxygen = 8
As we know that the atomic mass of oxygen = 16 amu
So, the approximate atomic mass of an oxygen atom in daltons (Da) = Atomic mass unit of oxygen = 16 amu = 16 Da
Thus, the approximate atomic mass of an oxygen atom daltons (Da) is, 16 Da
Three other pairs of liquids having different molecular masses can be tested to see if the pattern of boiling points will continue.
The boiling point of a liquid refers to the temperature at which the vapor pressure of the liquid is equal to the atmospheric pressure. Usually, the boiling point is affected by the nature of intermolecular forces in the compound.
In order to confirm whether or not the pattern of boiling point is correct, We have to get about three more pairs of compounds in which one has a lower molecular mass than the other and observe if the pattern in the values of boiling point will continue as predicted.
Learn more: brainly.com/question/8592296?
