BALANCING CHEMICAL EQUATIONS WORKSHEET

What is the pH of a buffer solution upon mixing 15.0 mL of 0.40 M HCl and 20.0 mL of 0.50 M NH? Kb (NH3) = 1.8 x 10 E. 7.00 A. 9

vladimir2022 [97]

Answer: The pH of resulting solution is 9.08

Explanation:

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

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

For HCl:

Molarity of HCl = 0.40 M

Volume of solution = 15.0 mL

Putting values in equation 1, we get:

$0.40M=\frac{\text{Moles of HCl}\times 1000}{15.0mL}\\\\\text{Moles of HCl}=0.006mol$

For ammonia:

Molarity of ammonia = 0.50 M

Volume of solution = 20.0 mL

Putting values in equation 1, we get:

$0.50M=\frac{\text{Moles of ammonia}\times 1000}{20.0mL}\\\\\text{Moles of ammonia}=0.01mol$

The chemical reaction for hydrochloric acid and ammonia follows the equation:

$HCl+NH_3\rightarrow NH_4Cl$

Initial: 0.006 0.01

Final: - 0.004 0.006

Volume of solution = 15.0 + 20.0 = 35.0 mL = 0.035 L (Conversion factor: 1 L = 1000 mL)

To calculate the pOH of basic buffer, we use the equation given by Henderson Hasselbalch:

$pOH=pK_b+\log(\frac{[salt]}{[base]})$

$pOH=pK_b+\log(\frac{[NH_4Cl]}{[NH_3]})$

We are given:

$pK_b$ = negative logarithm of base dissociation constant of ammonia = $-\log (1.8\times 10^{-5})=4.74$

$[NH_4Cl]=\frac{0.006}{0.035}$

$[NH_3]=\frac{0.004}{0.035}$

pOH = ?

Putting values in above equation, we get:

$pOH=4.74+\log(\frac{0.006/0.035}{0.004/0.035})\\\\pOH=4.92$

To calculate pH of the solution, we use the equation:

$pH+pOH=14\\pH=14-4.92=9.08$

Hence, the pH of the solution is 9.08

3 0

3 years ago

Homologous chromosomes pair up during prophase I to form a ________________.

Ksivusya [100]

I’m pretty sure the correct answer is “tetrad”

6 0

3 years ago

Lewis structure NCl3 please help me

natka813 [3]

Lewis structure :

•• •• ••
:Cl• •N • •Cl:
•• • ••
•
:Cl:
••

The dots around the respective atoms represent the number of valence electrons each of the corresponding atoms have. Since nitrogen is more electronegative it is placed within the middle, it can also form the 3 covalent bonds, unlike chlorine which can only form 1 and thus is in the middle of the diagram. This structure has gained stability in that all of the atoms have 8 electrons in its outermost shell, if you were to count the shared electrons for each atom.

8 0

3 years ago

what would happen to the volume of 10L carbon dioxide, if the pressure is doubled and temperature is constant?

lara [203]

Answer:

The volume will goes to decrease.

Explanation:

The given problem will be solved through the Boyle's law,

"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"

Mathematical expression:

P₁V₁ = P₂V₂

P₁ = Initial pressure