Give me lil reasoning so I know your not lying for points

Which reaction is an oxidation-reduction reaction?

sweet [91]

Answer:

pl

saponification palmitate

5 0

3 years ago

Calculate the ph of a dilute solution that contains a molar ratio of potassium acetate to acetic acid (pka ???? 4.76) of (a) 2:1

givi [52]

According to Hasselbach-Henderson equation:

$pH=pK_{a}+log\frac{[A^{-}]}{[HA]}$

Here, $[A^{-}]$ is concentration of conjugate base and [HA] is concentration of acid.

In the given problem, conjugate base is $CH_{3}COOK$ and acid is $CH_{3}COOH$ thus, Hasselbach-Henderson equation will be as follows:

$pH=pK_{a}+log\frac{[CH_{3}COOK]}{[CH_{3}COOH]}$ ...... (1)

(a) Ratio of concentration of potassium acetate and acetic acid is 2:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=2$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{2}{1}=5.06$

Therefore, pH of solution is 5.06.

(b) Ratio of concentration of potassium acetate and acetic acid is 1:3 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{1}{3}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{3}=4.28$

Therefore, pH of solution is 4.28.

(c)Ratio of concentration of potassium acetate and acetic acid is 5:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{5}{1}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{5}{1}=5.45$

Therefore, pH of solution is 5.45.

(d) Ratio of concentration of potassium acetate and acetic acid is 1:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=1$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{1}=4.76$

Therefore, pH of solution is 4.76.

(e) Ratio of concentration of potassium acetate and acetic acid is 1:10 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{1}{10}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{10}=3.76$

Therefore, pH of solution is 3.76.

4 0

3 years ago

Calculate the percentrage of neutral form of aspirin that is present in the stomach ph 1.

Korolek [52]

Answer:

The 99.68% of the aspirin is present in the neutral form

Explanation:

Aspirin, Acetylsalicylic acid, is a weak acid with pKa = 3.5

Using Henderson-Hasselbalch equation:

pH = pKa + log [A⁻] / [HA]

Where [A⁻] is the ionized form and HA the neutral form of the acid

Replacing with a pH of stomach of 1.0:

1.0 = 3.5 + log [A⁻] / [HA]

-2.5 = log [A⁻] / [HA]

3.16x10⁻³ = [A⁻] / [HA] (1)

A 100% of aspirin is = [A⁻] + [HA]

100 = [A⁻] + [HA] (2)

Replacing (2) in (1)

3.16x10⁻³ = 100 - [HA] / [HA]

3.16x10⁻³[HA] = 100 - [HA]

1.00316 [HA] = 100

[HA] = 99.68%

<h3>The 99.68% of the aspirin is present in the neutral form</h3>

8 0

3 years ago

How many atoms are in 3.5 moles of NaCl?

Ivenika [448]

Answer:

2.11 ×10²⁴ atoms

Explanation:

Given data:

Number of moles of NaCl = 3.5 mol

Number of atoms = ?

Solution:

It is known that 1 mole contain 6.022×10²³ atoms. The number 6.022×10²³ is called Avogadro number.

3.5 mol ×6.022×10²³ atoms / 1 mol

21.1 ×10²³ atoms

2.11 ×10²⁴ atoms

5 0

3 years ago

PLZ ANSWER

satela [25.4K]

Answer:

B. The student should model a convex lens because it directs light toward the center of the lens.

Explanation:

Lenses are optical devices that work on the principle of refraction.

Refraction is a phenomenon of wave (such as light waves) that occurs when a ray of light crosses the interface between two mediums with different optical density: when this occurs, the ray of light bends and change speed.

In particular, there are two types of lenses:

Convex lenses: these lenses are curved outward at their center, therefore the rays of light coming from infinite distance (parallel to the axis) are all focused into a point of the lens, called principal focus. Therefore, a convex lens directs lights towards this point.
Concave lenses: these lenses are curved inward at their center, therefore the rays of light coming from infinite distance are bent away from the principal focus. Therefore, this is a diverging lens, as the rays of light do not converge.

So, the correct answer is

B. The student should model a convex lens because it directs light toward the center of the lens.

7 0

3 years ago