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<em> Henderson-Hasselbach equation</em>:
Let's say we have a weak acid whose pKa is 7.0:
If the [A⁻]/[HA] ratio is 10/1, we're left with:
Now if the ratio is 1/10:
The difference in pH from one case to the other is (8.0-6.0) 2.0.
<em>So the pH changes by 2.0</em> if the [A-]/[HA] ratio of a base/weak acid mixture changes from 10/1 to 1/10.
<u>Keep in mind that no matter the value of pKa, the answer to this question will be the same.</u>
An element is just consisted of one type of atom and cannot be broken down by chemicals (Ex. Oxygen just has the oxygen molecule)
A compound is when there's a mixture of atoms and can be broken down by chemicals (Ex. NaCl is made up of sodium and chloride atoms)
Answer:
Mass = 381.28 g
Explanation:
Given data:
Number of moles of HNO₃ = 16 mol
Mass of Cu needed to react with 16 mol of HNO₃ = ?
Solution:
Chemical equation:
3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 4H₂O + 2NO
Now we will compare the moles of Cu with HNO₃ from balance chemical equation.
HNO₃ : Cu
8 : 3
16 : 3/8×16 = 6
Mass of Cu needed:
Mass = number of moles × molar mass
Mass = 6 mol × 63.546 g/mol
Mass = 381.28 g
Answer:
<h3>The answer is 7.85 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula
volume = final volume of water - initial volume of water
volume = 13.91 - 12 = 1.91 mL
We have
We have the final answer as
<h3>7.85 g/mL</h3>
Hope this helps you
