The wall would absorb extra heat during the day when the sun is out, then release the heat back into the room when the sun goes down.
True. A gas does not have a definite volume. Therefore, making this statement correct. <span />
Answer:
The molarity of this solution is 14.82 mol/dm3 or 14.82 mol/L
Explanation:
- Molarity is the number of mole present in 1 Litre of solution. Molarity of a solution is a term referred to as concentration of a solution. The unit of Molarity is Mol/dm3 or Mol/L.
- let us make an assumption that the volume of the ammonia solution is 1L or 1dm3. Also, 1L = 1000 mL.
Step 1: calculate the mass of the solution
Density = 0.90g/ml (from the question)
Density = mass/ volume
Therefore Mass = density x volume
= 0.90g/ml x 1000ml
mass = 900 g
Step 2: calculate the mass of NH3 present in the solution
Since the concentrated aqueous of ammonia is 28%, It signifies that 1000ml of the solution contains 28% Ammonia
Recall from the above calculation that the mass of 1000 ml of solution is 900 g.
Therefore the mass of ammonia will be 28% of 900 g
mass of NH3 = 0.28 x 900 g
= 252 g
Step 3: calculate the number of mole of NH3
mole = mass/ molar mass
molar mass of NH3 = 17 g/mol
Therefore mole of NH3 = 252/17
= 14.82 mol
Step 4: Calculate Molarity
Molarity = number of moles/ volume of solution in Litre (L)
Molarity = 14.82 / 1
Molarity = 14.82 mol/L
Answer:
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