So the molar mass of a Hydrogen molecule is 2. If you have 10 grams of Hydrogen molecules, you have 5 moles of Hydrogen molecules (10 moles of Hydrogen atoms). Avogadro's number is 6.0225x10^23. This means that one mole of a substance has that many particles.
Answer:
15 h
Explanation:
Okay, the first thing that we all have to know before we can answer this question is that this Topic that is, Chemistry of Radioactivity is related to kinetics in a way that Radioactive disintegration follows the first order of Reaction which is under kinetics. So, we will be using the first order kinetics rate law to answer this question. Using the equation (1) below;
k =[ 2.303/ t ]×log ([N°}/ [Nr]) --------(1).
We are given from the question that N° = initial sample = 0.8 mg and Nr= sample remaining = 0.2 and the time taken = t= 30.0 h.
k= (2.303/ 30.0 h ) × log (0.8/0.2).
k=0.076768 h^-1 × log (4).
k= 0.076768 h^-1 × 0.6021.
k= 0.0462 h^-1.
Therefore, using the formula for Calculating half life below for first order kinetics we will be able to find out answer.
k = ln 2/ t(1/2). Where t(1/2) is the half life.
t(1/2) = ln 2/ k.
t(1/2) = ln 2 / 0.0462 h^-1.
t(1/2)= 0.6931/0.0462 h^-1.
t(1/2)=15 h
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The new volume of air trapper in the cylinder is determined as 116.56 mL.
<h3>
New volume of air in the cylinder</h3>
The volume of air trapper in the cylinder is determined from Boyle's law;
P₁V₁ = P₂V₂
where;
- P₁ is initial pressure = 1.08 atm
- V₁ is initial volume = 145.7 mL
- P₂ is new pressure = 1.25 x 1.08 atm = 1.35 atm
- V₂ is new volume = ?
V₂ = (P₁V₁)/P₂
V₂ = (1.08 x 145.7)/1.35
V₂ = 116.56 mL
Thus, the new volume of air trapper in the cylinder is determined as 116.56 mL.
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Answer:
I think the first one
Explanation:
I'm not really sure but i count it
