Carrot carrot carrot carrot
Answer:
2.7 °C.kg/mol
Explanation:
Step 1: Calculate the freezing point depression (ΔT)
The normal freezing point of a certain liquid X is-7.30°C and the solution freezes at -9.9°C instead. The freezing point depression is:
ΔT = -7.30 °C - (-9.9 °C) = 2.6 °C
Step 2: Calculate the molality of the solution (b)
We will use the following expression.
b = mass of solute / molar mass of solute × kilograms of solvent
b = 102. g / (162.2 g/mol) × 0.650 kg = 0.967 mol/kg
Step 3: Calculate the molal freezing point depression constant Kf of X
Freezing point depression is a colligative property. It can be calculated using the following expression.
ΔT = Kf × b
Kf = ΔT / b
Kf = 2.6 °C / (0.967 mol/kg) = 2.7 °C.kg/mol
Answer:
Empirical CHO2
Molecular C2H2O4
Explanation:
To determine the formulas, firstly, we need to divide the percentage compositions by the atomic masses.
Kindly note that the atomic mass of carbon, oxygen and hydrogen are 12, 16 and 1 respectively. We proceed with the division as follows:
C = 26.7/12 = 2.225
H = 2.2/1 = 2.2
O = 71.1/16 = 4.44375
We then proceed to divide by the smallest value which is 2.2 in this case
C = 2.25/2.2 = 1
H = 2.2/2.2 = 1
O = 4.44375/2.2 = 2
Thus, the empirical formula is CHO2
We now proceed to get the molecular formula as follows
[12+ 1 + 16(2) ]n = 90.04
45n = 90.04
n = 90.04/45 = 2
The molecular formula is :
C2H2O4
The amount of product obtained in a chemical reaction. The absolute yield can be given as the weight in grams or in moles.
Answer:
(1) 4- ethyl -6 methyl -2 octyne
