Answer:
D) 5.15
Explanation:
Step 1: Write the equation for the dissociation of HCN
HCN(aq) ⇄ H⁺(aq) + CN⁻(aq)
Step 2: Calculate [H⁺] at equilibrium
The percent of ionization (α%) is equal to the concentration of one ion at the equilibrium divided by the initial concentration of the acid times 100%.
α% = [H⁺]eq / [HCN]₀ × 100%
[H⁺]eq = α%/100% × [HCN]₀
[H⁺]eq = 0.0070%/100% × 0.10 M
[H⁺]eq = 7.0 × 10⁻⁶ M
Step 3: Calculate the pH
pH = -log [H⁺] = -log 7.0 × 10⁻⁶ = 5.15
Choose all options that apply . Which of the following are steps necessary to ensure patient safety ? a) Make sure that the medication is dispensed in the same units in which it was prescribed. b ) Review any calculation questions with the pharmacist . Check to see if there's a better medication for the patient's problem. d) Dispense an extra dose to save the patient from having to return in case of loss or damage to one of the doses. Oe ) Compare the label on the medication with the order from the physician .
The Molecular Equation is as follow,
Ba(NO₃)₂ ₍aq₎ + MgSO₄ ₍aq₎ → BaSO₄ ₍s₎ + Mg(NO₃)₂ ₍aq₎
The Total Ionic Equation is as follow,
Ba²⁺₍aq₎ + 2NO₃⁻ ₍aq₎ +Mg²⁺ ₍aq₎ + SO₄²⁻ ₍aq₎ → Mg²⁺ ₍aq₎ + 2NO₃⁻ ₍aq₎ + BaSO₄ ₍aq₎
Here, Mg²⁺ and NO₃⁻ are spectator Ions,
So,
The Net Ionic Equation is as follow,
Ba²⁺ ₍aq₎ + SO₄²⁻ ₍aq₎ → BaSO₄ ₍aq₎
The solution for the question above is:
C = 0.270
<span>V = 0.0275L </span>
<span>n = ? </span>
<span>Use the molar formula which is: C = n/V </span>
<span>Re-arrange it to: n = CV </span>
<span>n = (0.270)*(0.0275) </span>
<span>n = 0.007425 mols </span>
<span>(more precise) n = 7.425 x 10^-3 mols
</span>
7.425 x 10^-3 mols is the answer.
Answer:
3
Explanation:
Zeros to the right of a decimal point after a value are sigificant, The leading zeros to reach the first digit ("1") are not. This has 3 sig figs: 120
