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2 years ago

Select the letter of a category on which you should focus when proofreading.

Chemistry

1 answer:

oee [108]2 years ago

8 0

B. Who, what, when, where, why, and how. Those are the most important and key componants in a story.

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NH3 is a weak alkali that does not dissociate fully into its solution. Which of the following is true about NH3?

ad-work [718]

<h2>NH3 is a weak alkali that does not dissociate fully into its solution. Which of the following is true about NH3? </h2><h2> </h2><h2>A. It has a very low pH. </h2><h2>B. It's dissociation is a reversible reaction. </h2><h2>C. It has a high H+ concentration. </h2><h2>D. It will release all of its OH- ions.</h2>

Explanation:

<h3>NH3 is a weak alkali that does not dissociate fully into its solution: It's dissociation is a reversible reaction. </h3><h3></h3>

Reactions are also :

Reversible
Irreversible

Reversible reaction

A reaction in which products can combine back to give reactants under same given condition .

Example : N₂+H₂-------NH₃

Irreversible reaction

A reaction in which the products cant combine back to give reactants under same set of conditions .

Example : Burning of paper

3 0

2 years ago

Read 2 more answers

A student dissolved 1.805g of a monoacidic weak base in 55mL of water. Calculate the equilibrium pH for the weak monoacidic base

yawa3891 [41]

Answer:

11.39

Explanation:

Given that:

$pK_{b}=4.82$

$K_{b}=10^{-4.82}=1.5136\times 10^{-5}$

Given that:

Mass = 1.805 g

Molar mass = 82.0343 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{1.805\ g}{82.0343\ g/mol}$

$Moles= 0.022\ moles$

Given Volume = 55 mL = 0.055 L ( 1 mL = 0.001 L)

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

$Molarity=\frac{0.022}{0.055}$

Concentration = 0.4 M

Consider the ICE take for the dissociation of the base as:

B + H₂O ⇄ BH⁺ + OH⁻

At t=0 0.4 - -

At t =equilibrium (0.4-x) x x

The expression for dissociation constant is:

$K_{b}=\frac {\left [ BH^{+} \right ]\left [ {OH}^- \right ]}{[B]}$

$1.5136\times 10^{-5}=\frac {x^2}{0.4-x}$

x is very small, so (0.4 - x) ≅ 0.4

Solving for x, we get:

x = 2.4606×10⁻³ M

pOH = -log[OH⁻] = -log(2.4606×10⁻³) = 2.61

5 0

2 years ago

Calculate the number of Na ions and Cl ions and total number of ions in 14.5g of NaCl.

Elanso [62]

Answer:

Number of Na ions in 14.5 g of NaCl is 1.49 × 10²³.

Number of Cl ions in 14.5 g of NaCl is 1.49 × 10²³.

Total number of ions = 1.49 × 10²³ + 1.49 × 10²³ = 2.98 × 10²³.

Explanation:

1 mole of any compound contains 6.023 × 10²³ molecules.

molecular weight of NaCl is 23 + 35.5 = 58.5 g.

so, 58.5 grams of NaCl makes 1 mole

⇒ 14.5 g of NaCl = $\frac{14.5}{58.5}$ = 0.248 moles.

⇒ 0.248 mole contains 0.248 × 6.023×10²³ molecules

= 1.49 × 10²³ molecules.

And 1 molecule contains 1 Na ion and 1 Cl ion.

⇒ number of Na ions in 14.5 g of NaCl is 1.49 × 10²³.

⇒ number of Cl ions in 14.5 g of NaCl is 1.49 × 10²³.

Total number of ions = 1.49 × 10²³ + 1.49 × 10²³ = 2.98 × 10²³.

6 0

3 years ago

Which of the following compounds has the highest boiling point?

anastassius [24]

Answer:

Butanoic acid

Explanation:

7 0

3 years ago

What is most likely oxidation state of aluminum (AI)?

blagie [28]

Aluminum has three oxidation states. The most common one is +3. The other two are +1 and +2. One +3 oxidation state for Aluminum can be found in the compound aluminum oxide, Al2O3.

7 0

2 years ago