Cations and what carry electrical charges through a solution

A barium hydroxide solution is prepared by dissolving 2.06 g of Ba(OH)2 in water to make 32.9 mL of solution. What is the concen

navik [9.2K]

Answer: 1.36 M

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n = moles of solute

To calculate the moles, we use the equation:

moles of solute= $\frac{\text {given mass}}{\text {molar mass}}=\frac{2.06g}{171g/mol}=0.0120moles$

$Molarity=\frac{0.0120\times 1000}{32.9}=0.364M$

The balanced reaction between barium hydroxide and perchloric acid:

$2HCIO_4+Ba(OH_)2\rightarrow BaCIO_4+2H_2O$

To calculate the concentration of acid, we use the equation given by neutralization reaction:

$n_1M_1V_1=n_2M_2V_2$

where,

$n_1,M_1\text{ and }V_1$ are the n-factor, molarity and volume of acid which is $HClO_4$

$n_2,M_2\text{ and }V_2$ are the n-factor, molarity and volume of base which is $Ba(OH)_2$

We are given:

$n_1=1\\M_1=?\\V_1=8.50mL\\n_2=2\\M_2=0.364M\\V_2=15.9mL$

Putting values in above equation, we get:

$1\times M_1\times 8.50=2\times 0.364\times 15.9\\\\M_1=1.36M$

Thus the concentration of the acid is 1.36 M

4 0

3 years ago

Why do a car's tires need more air in the winter than they do in the summer?

Hunter-Best [27]

Answer: Option (d) is the correct answer.

Explanation:

In winter's, temperature of atmosphere is low and due to this molecules of air present in the tire come closer to each other as they gain potential energy and loses kinetic energy.

Hence, air pressure decreases and there is need to fill more air in the tire.

Whereas is summer's, temperature is high so, molecules of air inside the tire gain kinetic energy and move rapidly from one place to another due to number of collisions. So, air pressure increases and there is no need to fill more air inside the tire.

Thus, we can conclude that the temperature is lower, so the air inside the tires contracts.

3 0

3 years ago

Read 2 more answers

Laney left a nail in water for two weeks, and the nail became rusted from sitting in the water.

Simora [160]

B) A chemical change because the nail reacts with water/oxygen to create rust (a type of oxide)

5 0

3 years ago

You dissolve 8.65 grams of lead(l) nitrate in water and then you add 2 50 grams of aluminum. This reaction occurs 2AI(S)+ 3Pb(NO

olga55 [171]

Answer: The theoretical yield of solid lead comes out to be 5.408 grams.

Explanation:

To calculate the moles, we use the following equation:

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

Moles of Lead nitrate:

Given mass of lead nitrate = 8.65 grams

Molar mass of lead nitrate = 331.2 g/mol

Putting values in above equation, we get:

$\text{Number of moles}=\frac{8.65g}{331.2g/mol}=0.0261moles$

Moles of Aluminium:

Given mass of aluminium = 2.5 grams

Molar mass of aluminium = 27 g/mol

Putting values in above equation, we get:

$\text{Number of moles}=\frac{2.5g}{27g/mol}=0.0925moles$

For the given chemical reaction, the equation follows:

$2AI(s)+3Pb(NO_3)_2(aq.)\rightarrow 3Pb(s)+2AI(NO3)_3(aq.$

By Stoichiometry:

3 moles of lead nitrate reacts with 2 moles of aluminium

So, 0.0261 moles of lead nitrate are produced by = $\frac{2}{3}\times 0.0261=0.0174moles$ of aluminium.

As, the required amount of aluminium is less than the given amount. Hence, it is considered as the excess reagent.

Lead nitrate is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

3 moles of lead nitrate are produces 3 moles of lead metal.

So, 0.0261 moles of lead nitrate will produce = $\frac{3}{3}\times 0.0261=0.0261moles$ of lead metal.

Now, to calculate the grams or theoretical yield of lead metal, we put in the mole's equation, we get:

Molar mass of lead = 207.2 g/mol

Putting values in above equation, we get:

$0.0261mol=\frac{\text{Given mass}}{207.2g/mol}$

Mass of lead = 5.408 grams

Hence, the theoretical yield of solid lead comes out to be 5.408 grams.

8 0

3 years ago

Why do oxygen and hydrogen can be kept underwater

Scrat [10]

The reason we cannot breath liquid water is because the oxygen used to make the water is bound to two hydrogen atoms and we cannot breath the resulting liquid

8 0

3 years ago