The problem can be solved using the following formula:
ΔTb = i Kb <em>m</em>
i = moles particles/moles solute
Kb = 0.512 °C/m
m = molality = moles solute/kg solvent
First we can solve for the molality of the solution:
75.0 g ZnCl₂ / 136.286 g/mol = 0.550 mol ZnCl₂
m = 0.550 mol/0.375 kg
m = 1.468 mol/kg
We can now solve for the change in temperature of the boiling point:
ΔTb = i Kb m
ΔTb = (3 mol particles/1 mol ZnCl₂) (0.512 °C/m) (1.468 m)
ΔTb = 2.25 °C
The boiling point of a solution is the initial boiling point plus the change in boiling point:
BP = 100 °C + 2.25 °C
BP = 102.25 °C
The solution will have a boiling point of 102.25 °C.
Answer:
6.25×10⁻⁶ g / cm³
Explanation:
Density is the relation between mass and volume as this formula shows.
Density of a compound = Mass of the compound / Volume of compound
In the values, we were given:
0.0124 kg / 1983 mm³ = 6.25×10⁻⁶ kg/mm³
This number means that in a volume of 1 mm³ of compound, the mass of it occupies 6.25×10⁻⁶ kg. Let's make a rule of three:
1 cm³ = 1×10⁻³ mm³
In 1 mm³ we have 6.25×10⁻⁶ kg of compound
So in 1×10⁻³ mm³ we would have (1×10⁻³ mm³ . 6.25×10⁻⁶ kg) / 1 mm³ =
6.25×10⁻⁹ kg
Now let's convert the kg to g.
1 kg = 1000 g
6.25×10⁻⁹ kg . 1000 = 6.25×10⁻⁶ g
Finally density is : 6.25×10⁻⁶ g / cm³
Answer:
The pressure of the gas after getting compressed is 1.92 L.
Explanation:
To calculate the new pressure, we use the equation given by Boyle's law. This law states that pressure is directly proportional to the volume of the gas at constant temperature.
The equation given by this law is:
(At constant temperature)
where,
are initial pressure and volume.
are final pressure and volume.
We are given:
Putting values in above equation, we get:
The pressure of the gas after getting compressed is 1.92 L.
A pure chemical compound is a chemical substance that is composed of a particular set of molecules or ions that are chemically bonded.
Answer:
Radioactive elements
Stable
Explanation:
Radioactive elements that have a longer half-life are more stable than those that a shorter half-life.
Half-life is the time taken for half of a radioactive element to decay by half of its original composition.
Now, if a substance have a long half-life, it is more stable and takes time to break down. For atoms with a short life, they are highly unstable and breaks down readily and easily.
