All categories

3 years ago

A reasonable pka for a weak base is: 10.3 0.9 5.8 7.4 13.1

Chemistry

1 answer:

andriy [413]3 years ago

7 0

Answer:

0.9

Explanation:

The pka represents the force by which the molecules need to dissociate for the acids ,

Hence , lower the pka stronger will be the acid and that therefore will dissociate completely and vice versa , for a weak acid higher the pka .

And in case of a base , it will be completely reversed , lower pKa , weaker base ,

and higher pKa , stronger base .

From the data of the question ,

0.9 is the lowest value of the pKa , hence , weakest base .

You might be interested in

As with other ionic compounds, potassium bromate, KBrO3, dissociates into ions when it dissolves in water. If 13.8 g of KBrO3 is

chubhunter [2.5K]

Answer:

ΔH of dissociation is 38,0 kJ/mol

Explanation:

The dissociation reaction of KBrO₃ is:

KBrO₃ → K⁺ + BrO₃⁻ 

This dissolution consume heat that is evidenced with the decrease in water temperature.

The heat consumed is:

q = CΔTm

Where C is specific heat of water (4,186 J/mol°C)

ΔT is the temperature changing (18,0°C - 13,0°C = 5,0°C)

And m is mass of water (150,0 mL ≈ 150,0 g)

Replacing, heat consumed is:

q = 3139,5 J ≡ 3,14 kJ

13,8 g of KBrO₃ are:

13,8 g×(1mol/167g) = 0,0826 moles

Thus, ΔH of dissociation is:

3,14kJ / 0,0826mol = 38,0 kJ/mol

I hope it helps!

3 0

2 years ago

What happened to the wind speeds of the storms?

oksano4ka [1.4K]

They would most likely speed up.

6 0

3 years ago

Find the [h3o ] in a sauvignon blanc with a ph of 3.24.

KengaRu [80]

Hello!

The H₃O⁺ concentration can be found using the definition of pH and clearing the equation for [H₃O⁺]. The solution has a pH lower than 7, so the Sauvignon Blanc is acid. The calculation for [H₃O⁺] is shown below:

$pH=-log [H_3O^{+}]$

$[H_3O^{+}]= 10^{-pH}=10^{-3,24}=0,00058M$

So, the concentration of H₃O⁺ in a Sauvignon Blanc with a pH of 3,24 is 0,00058 M

Have a nice day!

7 0

2 years ago

Which one of these are correct?

Sergio [31]

The correct answer is the one in the middle. Mixing food coloring and water

3 0

2 years ago

Which of the following best explains why you sanded the copper wire before burning it? to create less friction between the coppe

artcher [175]

The copper wire was sanded before burning in order to make sure that copper metal was exposed on the surface of the wire.

Answer: B

Explanation

The copper wire when placed in atmosphere without coating leads to oxidation of copper metal with respect to the impurities present in the atmosphere.

As copper is electropositive in nature, so electronegative ions present in the universe will try to react with copper and the copper will react easily with other elements.

So generally copper wire is coated with color or polymer coating.

In this case, the copper wire without any coating is sanded, so that the eddy sheets or polishing materials on friction with copper wire will remove the impurities by the electrostatic law of conservation of charges and charge transfer.

As the impurities are removed when copper wire is sanded, the copper atoms will be exposed on the surface of the wire leading to burning of copper in the copper wire.

8 0

2 years ago