All categories

4 years ago

Calculate molality of a 2m aq solution of sodium chloride with density 1.35g/mol

1 answer:

swat324 years ago

5 0

There are a number of ways to express concentration of a solution. This includes molarity and molality. Molarity is expressed as the number of moles of solute per volume of the solution while molality is expressed as the number of moles solute per mass of solution. Calculation is as follows:

(2 mol NaCl / L solution) ( 1 cm^3 / 1.35 g) ( 1000 L / 1 cm^3) (1000 g /kg) = 1.5 x 10^6 mol / kg solution

You might be interested in

Explain how liquid can enter the gas phase without reaching its boiling point

ioda

Evaporation is a phase transition from the liquid phase to the gas phase that occurs at temperatures below the boiling point at a given pressure.

hope this helps :)

4 0

3 years ago

Why are alcohols classified as organic compounds?

Maslowich

Rubbing Alcohols are chemical compounds because rubbing alcohol itself is a strecture made up of many different chemicals combinding in a compound that make, C3H8O

5 0

3 years ago

Explain the difference between a physical property and chemical property. Give examples of each.

MA_775_DIABLO [31]

A physical property is what a substance is like; it's directly observable. On the other hand, a chemical property is how a substance behaves; its reactivity.

Examples of a physical property are: color, texture, boiling point, freezing point, and melting point.

Examples of a chemical property are: flammability, combustion, and formation of a precipitate.

3 0

3 years ago

Extend your thinking: The slow decay of radioactive materials can be used to find the age of rocks, fossils, and archaeological

lisov135 [29]

The age in years of the Egyptian papyrus, the Aboriginal charcoal, the Mayan headdress, and the Neanderthal skull are 4000 years, 13106.5years , 2040 years, and 30353 years respectively.

<h3>What is the half-life of a radioactive material?</h3>

The half-life of a radioactive material is the time taken for half the atoms present in the material to decay or disintegrate.

The half-life, $t_\frac{1}{2}$ , the age, t, and amount remaining, $A_{r}$ , of a radioactive material are related by the formula below:

$t = \frac{t_\frac{1}{2}*A_{r}}{-ln2}$

Half-life of carbon-14 = 6000 years

For the Egyptian papyrus with 63% of its original carbon-14 atoms: $t = \frac{6000*0.63}{-0.63} = 4000\:years$

For the Aboriginal charcoal with 22% of its original carbon-14 atoms:

$t = \frac{6000*0.22}{-0.63} = 13106.5\:years$

For the Mayan headdress with 79% of its original carbon-14 atoms:

$t = \frac{6000*0.79}{-0.63} = 2040\:years$

Neanderthal skull with 3% of its original carbon-14 atoms:

$t = \frac{6000*0.03}{-0.63} = 30353\:years$

Therefore, the age in years of the Egyptian papyrus, the Aboriginal charcoal, the Mayan headdress, and the Neanderthal skull are 4000 years, 13106.5years , 2040 years, and 30353 years respectively.

Learn more about half-life at: brainly.com/question/26689704

#SPJ1

6 0

2 years ago

An industrial manufacturer wants to convert 175 kg of methane into HCN. Calculate the masses of ammonia and molecular oxygen req

Tema [17]

Given:

175 kilograms of Methane (CH4) to be synthesized into Hydrogen Cyanide (HCN)

The balanced chemical equation is shown below:

2 CH4<span> + 2 NH</span>3<span> + 3 O</span>2<span> → 2 HCN + 6 H</span>2<span>O
</span>
To calculate for the masses of ammonia and oxygen needed, our basis will be 175 kg CH4.

Molar mass:
CH4 = 16 kg/kmol
NH3 = 17 kg/kmol
O2 = 32 kg/kmol

mass of NH3 = 175 kg CH4 / 16 kg/kmol * (2/2) * 17 kg/kmol
mass of NH3 = 185.94 kg NH3 needed

mass of O2 = 175 kg CH4 / 16 kg/kmol * (3/2) * 32 kg/kmol
mass of O2 = 525 kg

mass of O = 525 kg / 32 kg/kmol * (1/2) * 16 kg/kmol
mass of O = 131.25 kg O

4 0

4 years ago