Calculate the molarity of a solution that contains 3.00 grams Na2SO4 in 25 mL of solution.

Chemistry

1 answer:

Naddik [55]3 years ago

3 0

Answer:

M Na2SO4 sln = 0.8448 M

Explanation:

molarity (M) [=] mol/L

∴ mass Na2SO4 = 3.00 g

∴ volume soln = 25 mL = 0.025 L

∴ molar mass Na2SO4 = 142.04 g/mol

⇒ mol Na2SO4 = (3.00 g)*(mol/142.04 g) = 0.02112 mol

⇒ M Na2SO4 sln = (0.02112 mol/0.025 L ) = 0.8448 M

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12. A beginner's bowling ball has a mass of 4.9 kg and a volume of 5.4 liters. Will it float in water,

Greeley [361]

Taking into account the definition of density and Archimedes' principle, the beginner bowling ball will float on the water.

But first it is neccesary to know that density is a quantity referred to the amount of mass in a certain volume of a substance or a solid object.

In other words, the density is the relationship between the weight (mass) of a substance and the volume that the same substance occupies.

The expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:

$density=\frac{mass}{volume}$

In this case, a beginner's bowling ball has a mass of 4.9 kg and a volume of 5.4 liters. This is:

mass= 4.9 kg= 4900 g (being 1 kg= 1000 kg)
volume= 5.4 L= 5400 mL (being 1L=1000 mL)

Replacing in the definition of density:

$density=\frac{4900 g}{5400 mL}$

Solving:

density=0.907 $\frac{g}{mL}$

On the other hand, Archimedes' principle says that an object immersed in a liquid experiences an upward vertical force equal to the weight of the volume of the dislodged liquid.

The sinking or floating of an object is determined by its density with respect to that of the liquid in which it is submerged.

Considering water as the liquid where the object is submerged in this case, an object with a higher density than water will sink. In contrast, an object with a lower density than water will float.

In this case, considering that water has a density of 1 $\frac{g}{mL}$ , the bowling ball for beginners has a lower density. This indicates that, having a lower density than water, the object will float.

In summary, the beginner bowling ball will float on the water.

Learn more about density: