<span>Kind of substance besides water:
The best example of hydrogen bonding excluding water is DNA. The two strands of polymers are connected by hydrogen bonds between the nucleotide bases</span>.
Answer:
Density is 2.7 grams
Explanation:
formula for density is p= mass over volume [p being density]. So all you have to do is divide
Answer:
Option A (9.0) is the correct alternative.
Explanation:
The given values are:
Molarity,
= 1.5 M
Volume,
= 6000 mL
or,
= 6 L
As we know,
⇒ 
or,
⇒ 
By putting the values, we get
Answer:
A. 32.06 g/mol
Explanation:
The molar mass units are always g/mol
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>.
