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3 years ago

The theory of plate tectonics is supported

1 answer:

5 0

Alfred Wegner was the first person to propose the idea that all seven continents were all one supercontinent called "Pangea". Everyone considered his theory to be a joke until he found evidence to back up his theory. His evidence was the matching mountain ranges, fossils, certain species, and more over different continents. Also that all the seven continents fit together like puzzle pieces. I hope this helps! :)

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Suppose 2.19g of barium acetate is dissolved of 15oml barium of a 0.10M acetate is dissolved in of a aqueous solution of sodium

Jobisdone [24]

The question is incomplete, here is the complete question:

Suppose 2.19 g of barium acetate is dissolved in 150 mL of a 0.10M of aqueous solution of sodium chromate. Calculate the final molarity of acetate anion in the solution. You can assume the volume of the solution doesn't change when the barium acetate is dissolved in it. Be sure your answer has the correct number of significant digits.

Answer: The final molarity of acetate ion in the solution is 0.12 M

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (in L)}}$ .....(1)

For Sodium chromate:

Molarity of sodium chromate solution = 0.10 M

Volume of solution = 150 mL

Putting values in equation 1, we get:

$0.10M=\frac{\text{Moles of sodium chromate}\times 1000}{150}\\\\\text{Moles of sodium chromate}=\frac{(0.10\times 150)}{1000}=0.015mol$

For barium acetate:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of barium acetate = 2.19 g

Molar mass of barium acetate = 255.43 g/mol

Putting values in above equation, we get:

$\text{Moles of barium acetate}=\frac{2.19g}{255.43g/mol}=0.0086mol$

The chemical equation for the reaction of barium acetate and sodium chromate follows:

$Ba(CH_3CO_2)_2+Na_2CrO_4\rightarrow BaCrO_4(s)+2Na^+(aq.)+2CH_3CO_2^-(aq.)$

By stoichiometry of the reaction:

1 mole of barium acetate reacts with 1 mole of sodium chromate

So, 0.0086 moles of barium acetate will react with = $\frac{1}{1}\times 0.0086mol$ of sodium chromate

As, given amount of sodium chromate is more than the required amount. So, it is considered as an excess reagent.

Thus, barium acetate is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

1 mole of barium acetate produces 2 moles of acetate ions

So, 0.0086 moles of barium acetate will produce = $\frac{2}{1}\times 0.0086=0.0172mol$ of acetate ion

Now, calculating the molarity of acetate ions in the solution by using equation 1:

Moles of acetate ion = 0.0172 moles

Volume of solution = 150 mL

Putting values in equation 1, we get:

$\text{Molarity of acetate ions}=\frac{0.0172\times 1000}{150}\\\\\text{Molarity of acetate ions}=0.12M$

Hence, the final molarity of acetate ion in the solution is 0.12 M

5 0

4 years ago

So guess what I did!!

Lapatulllka [165]

Answer:

what

Explanation:

what did u do

7 0

3 years ago

If anyone is good at chemistry do you mind helping? (●'◡'●)

stepladder [879]

• Before the balloon was placed inside the hot water, the pressure was the same inside and outside the balloon. The hot water raised the kinetic energy of the air molecules inside the balloon, expanding the balloon, through thermal expansion.

• (1) the pressure of air inside the balloon increased, (2) the volume of the inside of the balloon increased as well, and (3) the temperature of the balloon increased. Note that pressure and volume are inversely proportional, and pressure and temperature are directly proportional. Therefore as the temperature increases, the pressure inside will increase, causing an increase in the volume. At a certain point though the volume will increase too much as to cause a significant decrease in pressure.

• The air molecules will gain kinetic energy, hence (1) increasing the molecules's speed, and (2) heating the air molecules.

7 0

3 years ago

When the temperature of an object changes by 10 °C the same temperature change in Kelvins would be

kumpel [21]

The answer to this question would be: 10 °K

Kelvin and Celcius scales are different by 273 degrees but their ratio is the same. One degree in Kelvin is equal to one degree in Celcius. That mean, 10 °C change in Celcius would be same as 10 °K changes in Kelvin too.

8 0

3 years ago

How long does it take Earth to make one revolution?

andrew11 [14]

Answer:

365 days and five hours

8 0

3 years ago

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