Butylated hydroxytoluene (bht) is used as an antioxidant in processed foods. (it prevents fats and oils from becoming rancid.) a solution of 2.500 g of bht in 100.0 g of benzene had a freezing point of 4.880 oc. what is molecular mass of bht? . kf for benzene is 5.065 oc/m

Molecular mass of BHT is 204,2 g/mol

Explanation:

To answer this question you need to know that Freezing-point depression (A colligative property) is the decrease of the freezing point of a solvent on the addition of a non-volatile solute. The formula is:

ΔT = Kf m

Where ΔT is the freezing point depression (5,5°C - 4,880°C =  0,62°C

Kf that is freezing point molar constant of the solvent (5,065°C/m)

And m that is molality (moles of solute/kg of solvent). Replacing:

Knowing you have 100,0g of solvent ≡ 0,1000 kg:

= 0,01224 moles of solute ≡ BHT

As grams of BHT are 2,500, molecular mass of BHT is:

204,2 g/mol

I hope it helps

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.

the answer is minerals.