Answer:
4.87g
Explanation:
Step 1:
Data obtained from the question. This includes the following:
Mass of solution = 0.35kg
Molality = 0.238 m
Mass of NaCl =..?
Step 2:
Determination of the number of mole of NaCl in the solution.
Molality of a solution is simply defined as the mole of solute per unit kg of the solvent. It is given as:
Molality = mol of solute /mass of solvent (kg)
With the above formula, we calculate the mole of NaCl present in the solution as follow:
Molality = mol of solute /mass of solvent (kg)
0.238 = mol of NaCl /0.35
Cross multiply
mol of NaCl = 0.238 x 0.35
mol of NaCl = 0.0833 mol
Step 3:
Determination of the mass of NaCl in 0.0833 mol of NaCl.
This is illustrated below:
Number of mole NaCl = 0.0833 mol
Molar Mass of NaCl = 23 + 35.5 = 58.5g/mol
Mass of NaCl =..?
Mass = number of mole x molar Mass
Mass of NaCl = 0.0833 x 58.5
Mass of NaCl = 4.87g
Therefore, 4.87g of NaCl is contained in the solution.
Aufbau principle:
Electrons are added one at a time from the lowest energy orbitals available until all the orbitals are filled.
According to the Aufbau principle, electrons fill lower energy orbitals first.
(i) Boron (Z = 5)
Electronic configuration =
(ii) Neon (Z = 10)
Electronic configuration =
(iii) Aluminium (Z = 13)
Electronic configuration =
(iv) Chlorine (Z = 17)
Electronic configuration =
(v) Calcium (Z = 20)
Electronic configuration =
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Answer:
Sugar can be obtained by evaporation.
Filtering wont work because sugar is soluble in water thus will mix to form one layer.
