<span>1.23x10^24 atoms/6.022x10^23 atom/mol = 2.04 mol H20 </span>
Answer:
67.4 % of C₉H₈O₄
Explanation:
To make titrations problems we know, that in the endpoint:
mmoles of acid = mmoles of base
mmoles = M . volume so:
mmoles of acid = 20.52 mL . 0.1121 M
mmoles of acid = mg of acid / PM (mg /mmoles)
Let's determine the PM of aspirin:
12.017 g/m . 9 + 1.00078 g/m . 8 + 15.9994 g/m . 4 = 180.1568 mg/mmol
mass (mg) = (20.52 mL . 0.1121 M) . 180.1568 mg/mmol
mass (mg) = 414.4 mg
We convert the mass to g → 414.4 mg . 1g / 1000mg = 0.4144 g
We determine the % → (0.4144 g / 0.615 g) . 100 = 67.4 %
<span>Mr = 13 g / mol
mass = 5 g
Mol = 5/13 mol :)</span>
The rate constant : k = 9.2 x 10⁻³ s⁻¹
The half life : t1/2 = 75.3 s
<h3>Further explanation</h3>
Given
Reaction 45% complete in 65 s
Required
The rate constant and the half life
Solution
For first order ln[A]=−kt+ln[A]o
45% complete, 55% remains
A = 0.55
Ao = 1
Input the value :
ln A = -kt + ln Ao
ln 0.55 = -k.65 + ln 1
-0.598=-k.65
k = 9.2 x 10⁻³ s⁻¹
The half life :
t1/2 = (ln 2) / k
t1/2 = 0.693 : 9.2 x 10⁻³
t1/2 = 75.3 s
Answer:
Neon (Ne) has the most stable outer electron configuration because the outer electron is completely filled and it has octet structure
Explanation:
The configuration of these elements is as follows;
Cl₁₇ = 2, 8,7 (the outer electron is 7)
Ca₂₀ = 2,8,8,2 (the outer electron is 2)
Ne₁₀ = 2,8 (the outer electron is 8)
Na₁₁ = 2,8,1 (the outer electron is 1)
Based on the outer electron value above, Neon (Ne) has the most stable outer electron configuration because the outer electron is completely filled and it has octet structure.
