A standard of measurement system is important because it allows scientists to compare data and communicate with each other about their results.
Answer:
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
Explanation:
One colligative property is the freezing point depression due the addition of a solute. The equation is:
ΔT=Kf*m*i
<em>Where ΔT is change in temperature = 0.400°C</em>
<em>Kf is freezing point constant of the solvent = 1.86°C/m</em>
<em>m is molality of the solution (Moles of solute / kg of solvent)</em>
<em>And i is Van't Hoff constant (1 for a nonelectrolyte)</em>
Replacing:
0.400°C =1.86°C/m*m*1
0.400°C / 1.86°C/m*1 = 0.215m
As mass of solvent is 280.0g = 0.2800kg, the moles of the solute are:
0.2800kg * (0.215moles / 1kg) = 0.0602 moles of solute must be added.
The mass of ethylene glycol must be added is:
0.0602 moles * (62.10g / mol) =
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
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Answer:
Um, where is the article?
unit coversation
1.429 atm - 1086mmhg
9361 pa-9.36 KPa - 70.21 mmhg
725 mmhg -0.95 atm- 96.26 kpa
calculation
(a) 1 atm = 760 mmhg
1.429 atm = ?
1.429 x760/1 = 1086.34 mm hg
(B) 1 mmhg = 101.325 kpa
? =9361 KPa
9361 x1 /101.25 =70.21 mmhg
760 mm hg= 101.325 KPa
70.21 mm hg=?
70.21 x101.325/760 = 9.36 Kpa
(C ) 1 atm = 760 mmhg
? = 725
= 725 x1/ 760=0.95 atm
1 atm = 101.325 kpa
0.95 =?
0.95 x101.325/1 = 96.26 KPa
<h3>
Answer:</h3>
482.596 grams
<h3>
Explanation:</h3>
The relationship between moles, molar mass and mass of a compound is given by;
In this case;
The compound in question is P₂O₅
Molar mass of P₂O₅ = 141.94 g/mol
Rearranging the formula;
Mass = Moles × molar mass
Therefore;
Mass of P₂O₅ = 3.4 mol × 141.94 g/mol
= 482.596 grams
Therefore, mass of P₂O₅ is 482.596 grams
