Answer:
is b
Explanation:
es la b porque estpy estudiando lo mismo
Answer:
12.99
Explanation:
<em>A chemist dissolves 716. mg of pure potassium hydroxide in enough water to make up 130. mL of solution. Calculate the pH of the solution. (The temperature of the solution is 25 °C.) Be sure your answer has the correct number of significant digits.</em>
Step 1: Given data
- Mass of KOH: 716. mg (0.716 g)
- Volume of the solution: 130. mL (0.130 L)
Step 2: Calculate the moles corresponding to 0.716 g of KOH
The molar mass of KOH is 56.11 g/mol.
0.716 g × 1 mol/56.11 g = 0.0128 mol
Step 3: Calculate the molar concentration of KOH
[KOH] = 0.0128 mol/0.130 L = 0.0985 M
Step 4: Write the ionization reaction of KOH
KOH(aq) ⇒ K⁺(aq) + OH⁻(aq)
The molar ratio of KOH to OH⁻is 1:1. Then, [OH⁻] = 0.0985 M
Step 5: Calculate the pOH
We will use the following expression.
pOH = -log [OH⁻] = -log 0.0985 = 1.01
Step 6: Calculate the pH
We will use the following expression.
pH + pOH = 14
pH = 14 - pOH = 14 -1.01 = 12.99
Answer:
The final pressure is approximately 0.78 atm
Explanation:
The original temperature of the gas, T₁ = 263.0 K
The final temperature of the gas, T₂ = 298.0 K
The original volume of the gas, V₁ = 24.0 liters
The final volume of the gas, V₂ = 35.0 liters
The original pressure of the gas, P₁ = 1.00 atm
Let P₂ represent the final pressure, we get;
∴ The final pressure P₂ ≈ 0.78 atm.
IF magnesium sulfide reacts with oxygen in the air it will produce
magnesium oxide + sulfur (IV) oxide
<u><em>explanation</em></u>
magnesium sulfide burn in oxygen to produce magnesium oxide and sulfur (iv) oxide according to the equation below
2MgS +3O2 →2MgO +2SO2
that is 2 moles of MgS react with 3 moles of O2 to produce 2 moles of MgO and 2 moles of SO2
