How many sigma and pi bonds in propionic bond

36g of KOH dissolved in 800mL of water. What is the molality of the solution?

Bad White [126]

Answer:

0.80m of KOH

Explanation:

Molality is an unit of concentration defined as the ratio between moles of solute and kg of solvent.

In the problem, the solute is KOH and solvent is water.

Moles of 36g KOH -Molar mass: 56.1g/mol- are:

36g KOH × (1mol / 56.1g) = 0.642 moles of KOH

Now, as density of water is 1g/mL, mass of 800mL of water is:

800mL × (1g / mL) × (1kg / 1000g) = 0.800kg of water

Thus, molality is:

0.642moles of KOH / 0.800kg = 0.80m of KOH

5 0

2 years ago

If 36.9 mL of B2H6 reacted with excess oxygen gas, determine the actual yield of B2O3 if the percent yield of B2O3 was 75.7%. (T

zhuklara [117]

Answer: The actual yield of $B_2O_3$ is 60.0 g

Explanation:-

The balanced chemical reaction :

$B_2H_6(l)+3O_2(g)\rightarrow B_2O_3(s)+3H_2O(l)$

Mass of $B_2H_6$ = $Density\times Volume=1.131g/ml\times 36.9ml=41.7g$

$\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}$

$\text{Moles of} B_2H_6=\frac{41.7g}{27.668g/mol}=1.51moles$

According to stoichiometry:

1 mole of $B_2H_6$ gives = 1 mole of $B_2O_3$

1.51 moles of $B_2H_6$ gives = $\frac{1}{1}\times 1.51=1.51$ moles of $B_2O_3$

Theoretical yield of $B_2O_3=moles\times {Molar mass}}=1.14mol\times 69.62g/mol=79.3g$

Percent yield of $B_2O_3$ = $75.7\%$

$\%\text{ yield}=\frac{\text{Actual yield}}{\text{Theoretical yield}}\times 100$

$75.7\%=\frac{\text{Actual yield}}{79.3}\times 100$

${\text{Actual yield}}=60.0g$

Thus the actual yield of $B_2O_3$ is 60.0 g

7 0

2 years ago

Which processes occur during the second stage of technological design? Check all that apply.

Lena [83]

There is four stages of technological design:1. identify a problem or need.2. design a solution.3. implement, build, test the design.4. determine if the solution met the need.To design a solution is second stage of technological design.

3 0

2 years ago

Read 2 more answers

Carl's chemistry teacher asked him to make a 1 M sodium chloride solution. Carl measured 58.44 grams NaCl, added it to a volumet

Nastasia [14]

Answer:

After measuring the solute, Carl should first dissolve the solid in a small amount of DI water before diluting to the total volume.

Explanation:

To ensure that all the solute dissolves in the solution, first dissolve the solid in less than the total volume of solution needed.

4 0

2 years ago

Read 2 more answers

Which of the following statements correctly relates mutations and survival rates of plants?

Tasya [4]

Answer is: Mutations sometimes improve the chances of survival for a plant.
Mutations are very important because they change variability in populations and in that way enable evolutionary change.
There are three types of mutations:
1) good or advantageous mutations - improve the chances of survival for a plant.
2) bad or deleterious - decrease the chances of survival for a plant.
3) neutral - not affect he chances of survival for a plant.

3 0

2 years ago