All categories

3 years ago

Which structural adaptation would help a plant survive better in shady environment ?

1 answer:

kramer3 years ago

4 0

The answer is large leaves.

These enable the plant to absorb more of the scarce sunlight it receives, so it can create enough nutrients for it to survive.

You might be interested in

PLEASE HELP ASAP! BRAINLIEST WILL BE GIVEN PLEASE HELP!

inessss [21]

I think it is D I'm not positive

5 0

3 years ago

Read 2 more answers

Which natural resource is nonrenewable?

Veronika [31]

Oil or petroleum are nonrenewable resources, the others are renewable resources.

7 0

3 years ago

Read 2 more answers

Which of the following acids is the WEAKEST? The acid is followed by its Ka value.HF, 3.5 × 10^-4HNO2, 4.6 × 10^-4HCN, 4.9 × 10^

Mila [183]

Answer:

HCN

Explanation:

There are several factors that can tell us when an acid is stronger than another, which are the following:

1. The Polarity of the X - H Bond

2. Size of the X atom.

3. Charge on the acid.

4. Oxidation state of the central atom

5. Values of Ka and pKa.

From all of this factors, we can see that the exercise is already giving us values of Ka, and also we have different types of acid, not only with the form H - X

So, we will base the force of an acid by it's pKa value.

The pKa value which is calculated with the expression:

pKa = -logKa

pKa is a value that indicates how strong is the acid you are working with. This value can vary depending on factors such the charge of the acid. I f this charge can be easily distributed in resonance structures, the compound is more acidic, and therefore the pKa value is lower.

The lower the pKa, the more acidic the compound is.

So calculating the pKa on every structure we have:

HF: pKa = -log(3.5x10^-4) = 3.46

HNO2: pKa = -log(4.6x10^-4) = 3.34

HCN: pKa = -log(4.9x10^-10) = 9.31

HCOOH: pKa = -log(1.8x10^-4) = 3.74

HClO2: -log(1.1x10^-2) = 1.96

So according to all this values, we can conclude that the weakest acid is the HCN

4 0

3 years ago

g On the basis of their respective pKa values, determine which is the stronger acid, acetic acid (pKa 5 4.7) or benzoic acid (ma

ozzi

Answer:

Benzoic acid is the stronger acid

Explanation:

Weak acids do not dissociate completely in the solution. They exists in equilibrium with their respective ions in the solution.

The extent of dissociation of the acid furnising hydrogen ions can be determined by using dissociation constant of acid ( $K_a$ ).

Thus for a weak acid, HA

$HA \rightleftharpoons A^- + H^+$

The $K_a$ is:

$K_a= \frac{[A^-][H^+]}{[HA]}$

The more the $K_a$ , the more the acid dissociates, the more the stronger is the acid.

Also,

$pK_a$ is defined as the negative logarithm of $K_a$ .

So, more the $pK_a$ , less is the $K_a$ and vice versa

All can be summed up as:

The less the value of $pK_a$ , the more the $K_a$ is and the more the acid dissociates and the more the stronger is the acid.

Given,

$pK_a$ of acetic acid = 54.7

$pK_a$ of benzoic acid = 54.2

$pK_a$ of benzoic acid < $pK_a$ of acetic acid

So, benzoic acid is the stronger acid.

5 0

3 years ago

Which of the following mixtures will react the fastest?

olga2289 [7]

Answer:

I think the answer would be A.

8 0

3 years ago