Identifying Physical and Chemical Chang

Chemistry

1 answer:

Burka [1]3 years ago

3 0

The answer is true because water and oxygen make up physical change

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Calculate how many grams would be required to prepare 600. 0 ml of 0. 150 m of naf? molar mass of naf is 41. 9 g/mo

marta [7]

Considering the definition of molarity and molar mass, the mass of NaF required is 3.771 grams.

<h3>Definition of molarity</h3>

Molar concentration or molarity is a measure of the concentration of a solute in a solution and indicates the number of moles of solute that are dissolved in a given volume.

The molarity of a solution is calculated by dividing the moles of solute by the volume of the solution:

$molarity=\frac{number of moles}{volume}$

Molarity is expressed in units $\frac{moles}{liters}$ .

<h3>Definition of molar mass</h3>

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

<h3 /><h3>Mass of NaF required</h3>

In this case, you know:

molarity= 0.15 M= 0.15 $\frac{moles}{L}$
number of moles= ?
volume= 600 mL= 0.6 L

Replacing in the definition of molarity:

$0.15\frac{moles}{L} =\frac{number of moles}{0.6 L}$

Solving:

0.15 $\frac{moles}{L}$ × 0.6 L= number of moles

<u><em>0.09 moles= number of moles</em></u>

The molar mass of NaF is 41. 9 g/mol. So, you can apply the following rule of three: If by definition of molar mass 1 mole of the compound contains 41.9 grams, 0.09 moles of the compound contains how much mass?

$mass=\frac{0.09 molesx41.9 grams}{1 mole}$