All categories

3 years ago

If the [A-]/[HA] ratio of a base/weak acid mixture changes from 10/1 to 1/10, how much does the pH change:

Chemistry

1 answer:

andreev551 [17]3 years ago

3 0

Answer:

The pH changes by 2.0 if the [A-]/[HA] ratio of a base/weak acid mixture changes from 10/1 to 1/10.

Explanation:

To solve this problem we use the Henderson-Hasselbach equation:

pH = pKa + log [A⁻]/[HA]

Let's say we have a weak acid whose pKa is 7.0:

pH = 7.0 + log [A⁻]/[HA]

If the [A⁻]/[HA] ratio is 10/1, we're left with:

pH = 7.0 + log (10/1)

pH = 7.0 + 1

pH = 8.0

Now if the ratio is 1/10:

pH = 7.0 + log (1/10)

pH = 7.0 - 1

pH = 6.0

The difference in pH from one case to the other is (8.0-6.0) 2.0.

So the pH changes by 2.0 if the [A-]/[HA] ratio of a base/weak acid mixture changes from 10/1 to 1/10.

Keep in mind that no matter the value of pKa, the answer to this question will be the same.

You might be interested in

You have at your disposal 3 1-pound bags of various pure salts that dissolve readily in water. You can add one of the bags to a

Sedaia [141]

Answer:

This question appears incomplete

Explanation:

However, it should be noted that addition of soluble salts generally lowers the freezing point of water hence after the addition, water will no longer freeze at 0°C but lower.

Soluble salts tend to form more ions in water, it is these ions that are responsible for interfering with the hydrogen bonds hence lowering the freezing. Thus, (since each bag are of the same weight) the bag that contains the salt that ionizes more in water will lower the freezing point by the greatest amount.

NOTE: Different weight of the salts could lead to more ions been formed in the water by some salts as against the other.

6 0

4 years ago

A satellite and a hockey puck are alike because they illustrate Newton's first law of motion.

lutik1710 [3]

Answer:

It would be True

Explanation:

Because they both have the same push of gravity. Gravity affects all objects equally. If you drop an egg and a watermelon at the same time they would both collide with the floor at the same time.

8 0

3 years ago

For a school event 1/6 of the athletic field is reversed for the fifth -grade classes the reserved part of the field is divided

SVETLANKA909090 [29]

Answer:

$\frac{1}{24}$

Explanation:

Given:

For a school event, 1/6 of the athletic field is reserved for the fifth -grade classes and the reserved part of the field is divided equally among the 4 fifth grade classes in the school.

To find: fraction of the whole athletic field reserved for each fifth class

Solution:

Fraction of the whole athletic field reserved for four fifth classes = $\frac{1}{6}$

So, fraction of the whole athletic field reserved for each fifth class = $\frac{1}{4}(\frac{1}{6})=\frac{1}{24}$

3 0

3 years ago

When a glow stick is crushed and shaken, the two liquids mix and the stick glows.

Mars2501 [29]

Answer:

A chemical change has occurred, with energy being given off.

Explanation:

The liquids mix and the stick gives off energy in light form

3 0

3 years ago

1 pentagram equals how many grams

Fofino [41]

Answer:

5 grams.

Explanation:

Anything that weighs 5 grams, technically, is a pentagram.

7 0

3 years ago