Correct Answer: Option g: <span>adding salt to water lowers its freezing point
Reason:
Freezing point is a colligative property. When a non-volatile solution is present in solution, it's freezing point decreases. This is referred as depression in freezing point (</span>ΔTf<span>). Extent of lowering in freezing point is dependent on number of particles present in system. Mathematically it is expressed as:
</span>ΔTf = Kf X m
<span>
where, m = molality of solution
Kf = cryoscopic constant.
Hence, a</span><span>dding salt to water lowers the freezing point of solution.</span>
Answer:
The parcial pressure of N₂ in the mixture is 1.24 atm.
Explanation:
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
PT = PA + PB
This relationship is due to the assumption that there are no attractive forces between the gases.
In this case:
PT=PHe + PNe + PN₂
You know:
- PT= 1.943 atm
- PHe= 0.137 atm
- PNe= 0.566 atm
- PN₂= ?
Replacing:
1.943 atm= 0.137 atm + 0.566 atm + PN₂
Solving:
1.943 atm= 0.703 atm + PN₂
1.943 atm - 0.703 atm= PN₂
1.24 atm= PN₂
<u><em>The parcial pressure of N₂ in the mixture is 1.24 atm.</em></u>
The molarity of a Sodium carbonate solution : 0.373 M
<h3>Further explanation</h3>
Given
32.52 g Na₂CO₃
822 ml of solution = 0.822 L
Required
The molarity
Solution
Molarity shows the number of moles of solute in every 1 liter of solution.
mol of solute = mol of Na₂CO₃ :
= mass : MW Na₂CO₃
= 32.52 g : 106 g/mol
= 0.307
Molarity :
= n : V
= 0.307 mol : 0.822 L
= 0.373 M
2.4368 MILOGRAMS is burned
