Answer:
pH of buffer is 4.81
Explanation:
The reaction between HCl and sodium acetate will product acetic acid. The presence of weak acid (acetic acid) and its salt will make a buffer.
The reaction will be:

Thus one mole each of HCl and acetate will give one mole of acetic acid.
The moles of HCl present = molarity X volume = 0.452 X 0.204 =0.092
moles of acetic acid formed on reaction of HCl with acetate = 0.092
Initial moles of sodium acetate present = molarity X volume = 0.4X0.5 =0.2
moles of sodium acetate left =0.108 mol
the pKa of acetic acid =4.74
The pH of buffer is calculated using Henderson Hassalbalch's equation :
pH = pKa + log![\frac{[salt]}{[acid]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D)

Answer:
the mass of potassium nitrate would be needed to produce a saturated solution of potassium nitrate in 50 grams of water at 313 K is

Explanation:
To determine the mass of potassium nitrate needed to
produce a saturated solution of potassium nitrate in 50 grams of water at 313 K?, then it implies that we need to determine the
solubility of KNO3 is 62g KNO3 in 100g H2O at 313K. And this simply the amount of solute that when it dissolved in that water, then the water will not be able to take more solute again which means it has been saturated.that is the maximum quantity that the water can take at 313K.
If the solubility of KNO3 is 62g KNO3 in 100g H2O at temperature 313K
Then 50 g of water contains potassium nitrate = (62/100 X 50) at 313k = 31g
Therefore, the mass of potassium nitrate would be needed to produce a saturated solution of potassium nitrate in 50 grams of water at 313 K is
31g
To calculate the average mass of the element, we take the summation of the product of the isotope and the percent abundance. In this case, it is 0.935 * 268.9 amu + 0.065* 269.9 amu. This is equal to an average mass of 268.965 amu.
Answer:
A. Solid aluminum oxide and solid iron
Explanation:
The reaction equation is given as:
2Al + Fe₂O₃ → Al₂O₃ + 2Fe
The species on the left hand side are the reactants
Those on the right hand side of the expression are the products.
The products are:
Al₂O₃ and Fe
These are solid aluminum oxide and solid iron
Fossil fuels are mostly the major source of energy