<span>A 50-gram sample with a half-life of 12 days will have a remaining mass of 25 grams after its 12-day half-life.
Every cycle of a half-life, the sample will lose half of its mass, so if the half-life, itself, is 12 days and the time period passing is 12 days, one half-life has passed and the material will be halved.</span>
PH is calculated using <span>Handerson- Hasselbalch equation,
pH = pKa + log [conjugate base] / [acid]
Conjugate Base = Acetate (CH</span>₃COO⁻)
Acid = Acetic acid (CH₃COOH)
So,
pH = pKa + log [acetate] / [acetic acid]
We are having conc. of acid and acetate but missing with pKa,
pKa is calculated as,
pKa = -log Ka
Putting value of Ka,
pKa = -log 1.76 × 10⁻⁵
pKa = 4.75
Now,
Putting all values in eq. 1,
pH = 4.75 + log [0.172] / [0.818]
pH = 4.072
The correct values I believe would be a=1 b=-2 and c=-3.
Answer:
21.8 g/mol
Explanation:
Molecular weight of CH4 = 16g/mol
H2 = 2g/mol
N2 = 28g/mol
(16*30 + 2*10 + 28*60)/100
=2180/100
=21.8g/mol
<span>It takes 3 breaths to get to 1.2 l. One breath is then (1.2 l) / 3 breaths = .4l/breath.
To get to 3.0 l we need the difference from 1.2 l.
3.0-1.2 = 1.8 l.
Divide the difference by liters/breath (.4) to get how many needed breaths.
(1.8 l)/(.4 l/breath) = 4.5 breaths to get the balloon to 3.0 l.
In total there were 3 breaths+ 4.5 breaths = 7.5breaths to get to 3.0 l.
To find the total moles multiply 7.5breaths by .060 moles/breath
7.5 breaths*.060moles/breath = .45moles</span>