Answer:
333.7g of antifreeze
Explanation:
Freezing point depression in a solvent (In this case, water) occurs by the addition of a solute. The law is:
ΔT = Kf × m × i
Where:
ΔT is change in temperature (0°C - -20°C = 20°C)
Kf is freezing point depression constant (1.86°C / m)
m is molality of solution (moles solute / 0.5 kg solvent -500g water-)
i is Van't Hoff factor (1, assuming antifreeze is ethylene glycol -C₂H₄(OH)₂)
Replacing:
20°C = 1.86°C / m × moles solute / 0.5 kg solvent × 1
5.376 = moles solute
As molar mass of ethylene glycol is 62.07g/mol:
5.376 moles × (62.07g / 1mol) = <em>333.7g of antifreeze</em>.
The answer is B. Acid turns blue litmus paper to red
Answer:
Mole fraction H₂ = 0.29
Partial pressure of H₂ → 88.5 kPa
Explanation:
You need to know this relation to solve this:
Moles of a gas / Total moles = Partial pressure of the gas / Total pressure
Total moles = 3 mol + 7.3 mol → 10.3 moles
Mole fraction H₂ → 3 moles / 10.3 moles = 0.29
Mole fraction = Partial pressure of the gas / Total pressure
0.29 . 304 kPa = Partial pressure of H₂ → 88.5 kPa
Answer:
0.0123 moles
Explanation:
Concentration = Moles / Volume of solution
or you can rearrange the formula to get
Moles = concentration (moles/liter) x volume of solution (liter)
First convert your volume to L instead of mL. 35mL = 0.035L
moles = 0.350 moles/liter x 0.035 liter (liters cancel out)
moles = 0.0123
Answer:A pseudo-noble gas configuration is: 1s2 2s2 2p6 3s2 3p6 3d10. Cu^+ has this electron configuration. The answer is C)
Explanation:
