The number of half -lives that has passed after 105 hours for krypton-79 that has half-life of 35 hours is calculated as below
if 1 half life = 35 hours
what about 105 hours = ? half-lives
= (1 half life x105 hours) /35 hours = 3 half-lives has passed after 105 hours
The subatomic particle involved in chemical bonding is the electron. Electrons are the smallest of all subatomic particles and orbit the nucleus in discrete energy levels called shells. Electrons are negatively charged and the nucleus is positively charged due to the protons.
Answer:
The answer is given below.
Explanation:
We will consider the acid as HA and will set up an ICE table with the equilibrium dissociation of α.
AT pH 2.4 the initial H+ concentration will be 3.98^10-3 M
HA → H+ + A-
Initial concentration: 0.1 → 3.98 ^10-3 + 0
equilibrium concentration: 0.1(1-α) → 3.98 * 10-3 + 0.1α 0.1α
pKa of chloroacetic acid is 2.9
-log(Ka) = 2.9
Ka = 1.26 * 10-3
From the equation, Ka = [H+] * [A-] / [HA]
1.26 * 10-3 = (3.98 * 10-3 + 0.1α )* 0.1α / 0.1(1-α)
Since α<<1, we assume 1-α = 1
Solving the equation, we have: α = 0.094
Since this is the fraction of acid that has dissociated, we can say that % of base form = 100 * α= 9.4%
The moles of O2 are needed to react completely with 1.00 mol of C₂H₂ is 5 mol , 0.23 moles of C₂H₂ are needed to form 0.46 mol of CO₂ .
<h3>What is a Balanced Reaction ?</h3>
A balanced reaction is a reaction in which the number of atoms present in the reactants is equal to the number of atoms in the products.
It is given in the question that
the combustion of Acetylene is given by
2 H―C≡C―H + 5 O₂ → 4 CO₂ + 2 H₂O
Given moles of Acetylene = 1 mol
Moles of oxygen needed = 5 mol
as the mole fraction of Acetylene to Oxygen is 1 :5
The mole of Acetylene needed to form 0.46 mol of CO₂ is ?
mole fraction of CO₂ to Acetylene is 4:2
Therefore 0.23 moles of CO₂ is required.
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Specific heat capacity, which is measured in J/g-°F