Answer : The pressure in torr and in atmospheres are, 745 torr and 0.980 atm respectively.
Explanation :
As we are given that the atmospheric pressure is, 745 mmHg.
Now we have to determine the pressure in torr and atm.
Conversions used:
1 atm = 760 mmHg
1 atm = 760 torr
1 mmHg = 1 torr
As, 760 mmHg = 1 atm
So, 745 mmHg =
and,
As, 1 mmHg = 1 torr
So, 745 mmHg = 745 torr
Therefore, the pressure in torr and in atmospheres are, 745 torr and 0.980 atm respectively.
The statement that best describes a buffer is: <u>A buffer resists change in pH by accepting hydrogen ions when acids are added to the solution and donating hydrogen ions when bases are added.</u>
Why?
A buffer is a solution made by combining either:
- A weak acid (HA) and its conjugate base (A⁻).
- A weak base (B) and its conjugate acid (HB⁺)
The purpose of a buffer is to resist changes in pH when a strong acid or base is added to the solution.
If the buffer is composed of HA and A⁻ and a strong acid (e.g. HCl) is added, the buffer <u>accepts hydrogen ions</u> in the following way:
A⁻+HCl → HA+Cl⁻
If a strong base (e.g. NaOH) is added, the buffer donates hydrogen ions in the following way:
HA + NaOH → NaA + H₂O
The pH of the buffer at any given moment can be found by using the Henderson-Hasselbach equation, based on the equilibrium HA + H₂O ⇄ H₃O⁺ + A⁻
Have a nice day!
Answer:
Complete ionic: .
Net ionic: .
Explanation:
Start by identifying species that exist as ions. In general, such species include:
- Soluble salts.
- Strong acids and strong bases.
All four species in this particular question are salts. However, only three of them are generally soluble in water: , , and . These three salts will exist as ions:
- Each formula unit will exist as one ion and one ion.
- Each formula unit will exist as one ion and two ions (note the subscript in the formula .)
- Each formula unit will exist as one and two ions.
On the other hand, is generally insoluble in water. This salt will not form ions.
Rewrite the original chemical equation to get the corresponding ionic equation. In this question, rewrite , , and (three soluble salts) as the corresponding ions.
Pay attention to the coefficient of each species. For example, indeed each formula unit will exist as only one ion and one ion. However, because the coefficient of in the original equation is two, alone should correspond to two ions and two ions.
Do not rewrite the salt because it is insoluble.
.
Eliminate ions that are present on both sides of this ionic equation. In this question, such ions include one unit of and two units of . Doing so will give:
.
Simplify the coefficients:
.
C2H2O4 C2HO4- + H+
0.175 - x x x + y
C2HO4- c2o42– + H+
x - y y x + y
K2 = (y) (x +y) / (x-y)
As, y << x
So, K2 = (y) (x) / (x)
K2 = y =6.1 × 10^–5
Hence, concentration of (c2o42–) 6.1 × 10^–5 M
Answer:
276g
Explanation:you are adding salt to water the mass is not destroyed so you just add the numbers hope this helps god bless