Answer:
- Last choice: <em><u>- 3.72°C</u></em>
Explanation:
The freezing point depression in a solvent is a colligative property: it depends on the number of solute particles.
The equation to predict the freezing point depression in a solvent is:
Where,
- ΔTf is the freezing point depression of the solvent,
- Kf is the cryoscopic molal constant of the solvent, and i is the Van'f Hoff factor, which is the number of ions produced by each unit formula of the ionic compound.
The calcualtions are in the attached pdf file. Please, open it by clicking on the image of the file.
Answer:
Iron remains = 17.49 mg
Explanation:
Half life of iron -55 = 2.737 years (Source)
Where, k is rate constant
So,
The rate constant, k = 0.2533 year⁻¹
Time = 2.41 years
= 32.2 mg
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
So,
<u>Iron remains = 17.49 mg</u>
Answer:
Explanation:
The formula relating the mass m of a sample and the heat q to vaporize it is
q = mL, where L is the latent heat of vaporization.

Answer:
There is 2.52 kJ of energy released (option 4)
Explanation:
Step 1: Data given
The enthalpy of fusion of methanol (CH3OH) is 3.16 kJ/mol
Mass of methanol = 25.6 grams
Molar mass of methanol = 32.04 g/mol
Step 2: Calculate moles of methanol
Moles methanol = mass methanol / molar mass methanol
Moles methanol = 25.6 grams / 32.04 g/mol
Moles methanol = 0.799 moles
Step 3: Calculate energy transfer
Energy transfer = moles * enthalpy of fusion
Energy = 0.799 moles * 3.16 kJ/mol
Energy = 2.52 kJ released
There is 2.52 kJ of energy released
Answer:
(C) im pretty sure is the answer
Explanation: