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.
Answer:
It's The amount of matter within the system remains the same and The cycle has a well-defined starting and stopping point.
Explanation:
The ice will require two forms of heat: latent to melt and sensible to be heated to 50 °C.
Q(ice) = ml + mCpΔT
= 150 x 333 + 150 x 4.18 x 50
= 85950 Joules
The mass of steam must release this much energy in two forms: latent to fuse into water and then sensible to cool to 50 °C.
85950 = m(2256) + 4.18 x 50 x m
m = 34.9 grams of steam.
to have the closest number rounded up
