Answer:
66.7s
Explanation:
Let's bring out the parameters we were given...
Half life = ?
Initial Concentration = 0.0576 M
Final Concentration = 0.0249 M
Time for the concentration change to occur = 97.8s - 17.1s = 80.7s
Formular for half life (t1/2) is given as;
t1/2 = ln2 / k ≈ 0.693 / k
where k = rate constant
From the formular of first order reactions;
ln[A] = ln[A]o − kt
where [A] = Final Concentration and [A]o = Initial Concentration
Inserting the values, we have;
ln(0.0249) = ln(0.0576) - k(80.7)
Upon solving for k, we have;
-0.8387 = -k(80.7)
k = 0.01039 s−1
t1/2 = 0.693 / k = 0.693 / 0.01039 = 66.7s
Answer:
CaCO3 (s) → CaO (s) + CO2 (g)
The mass of carbonate that must have reacted was 43.03 grams
Explanation:
CaCO3 → CaO + CO2
Relation between reactant and product is 1:1
Let's apply the Ideal Gas Law to find out the moles of CO2 which were produced.
P . V = n . R . T
1 atm . 23 L = n . 0.082 L.atm/mol.K . 653K
(1atm . 23L) / (0.082 mol.K/L.atm . 653K) = n
0.43 moles = n
0.43 moles of CO2, were produced from 0.43 moles of CaCO3.
Molar weight of CaCO3 = 100.08 g/m
Mass = Molar weight . moles
Mass = 100.08 g/m 0.43 m = 43.03 g
Mass of Magnesium nitrate produced : 593.2 g
<h3>Further explanation</h3>
The reaction equation is the chemical formula of reagents and product substances
A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.
Reaction
2HNO₃ + Mg(OH)₂ → Mg(NO₃)₂ + 2H₂0
mol HNO₃ = 8
From the equation, mol ratio of HNO₃ : Mg(NO₃)₂ = 2 : 1, so mol Mg(NO₃)₂ :
Mass Mg(NO₃)₂(MW=148,3 g/mol) :
One correct thging is that there are the same amount of positive and negative atoms
The balanced equation for the reaction is
CO(g) + 2H₂(g) ⇄ CH₃<span>OH(g)
Since given concentrations are at equilibrium state, the expression for the equilibrium constant, k can be written as
k = [</span>CH₃OH(g)] / [CO(g)] [H₂(g) ]²
By substitution,
k = 0.030 M / 0.020 M x (<span>0.072 M</span>)²
k = 289.35 M⁻²
