Answer:
A. Wipe down the glassware to remove any cleaning solvent.
Explanation:
· Remove stoppers and stopcocks when they are not in use. Otherwise, they may "freeze" in place. You can de-grease ground glass joints by wiping them with a lint-free towel soaked with ether or acetone. Wear gloves and avoid breathing the fumes. The deionized water rinse should form a smooth sheet when poured through clean glassware.
Answer:
pH = 3.49
Explanation:
We have a buffer system formed by a weak acid (HNO₂) and its conjugate base (NO₂⁻ coming from KNO₂). We can calculate the pH of a buffer ssytem using the Henderson-Hasselbach equation.
pH = pKa + log [base] / [acid]
pH = -log Ka + log [NO₂⁻] / [HNO₂]
pH = -log 4.50 × 10⁻⁴ + log 0.290 M / 0.210 M
pH = 3.49
Answer:
True
Explanation:
Natural gas. Natural is its name. (I think)
Answer:
6.46 × 10⁻¹¹ M
Explanation:
Step 1: Given data
pH of the solution: 3.81
Step 2: Calculate the pOH of the solution
We will use the following expression.
pH + pOH = 14.00
pOH = 14.00 - pH = 14.00 - 3.81 = 10.19
Step 3: Calculate the concentration of OH⁻ ions
We will use the definition of pOH.
pOH = -log [OH⁻]
[OH⁻] = antilog -pOH = antilog -10.19 = 6.46 × 10⁻¹¹ M
