Answer:
0.0055 mol of N2O5 will remay after 7 min.
Explanation:
The reaction follows a first-order.
Let the concentration of N2O5 after 7 min be y
Rate = Ky = change in concentration of N2O5/time
K is rate constant = 6.82×10^-3 s^-1
Initial concentration of N2O5 = number of moles/volume = 2.1×10^-2/1.8 = 0.0117 M
Change in concentration = 0.0117 - y
Time = 7 min = 7×60 = 420 s
6.82×10^-3y = 0.0117 - y/420
0.0117 - y = 420×6.82×10^-3y
0.0117 - y = 2.8644y
0.0117 = 2.8644y + y
0.0117 = 3.8644y
y = 0.0117/3.8644 = 0.00303 M
Number of moles of N2O5 left = y × volume = 0.00303 × 1.8 = 0.0055 mol (to 2 significant digits)
Answer:
χH₂ = 0.4946
χN₂ = 0.4130
χAr = 0.0923
Explanation:
The total pressure of the mixture (P) is:
P = pH₂ + pN₂ + pAr
P = 443.0 Torr + 369.9 Torr + 82.7 Torr
P = 895.6 Torr
We can find the mole fraction of each gas (χ) using the following expression.
χi = pi / P
χH₂ = pH₂ / P = 443.0 Torr/895.6 Torr = 0.4946
χN₂ = pN₂ / P = 369.9 Torr/895.6 Torr = 0.4130
χAr = pAr / P = 82.7 Torr/895.6 Torr = 0.0923
Atomic mass / mass number / atomic weight
(all of which mean the same thing)
The mole<span> is the </span>unit of measurement<span> in the </span>International System of Units<span> (SI) for </span>amount of substance<span>. It is defined as the </span>amount<span> of a </span>chemical substance<span> that contains as many representative particles, e.g., </span>atoms<span>, </span>molecules<span>, </span>ions<span>, </span>electrons<span>, or </span>photons<span>, as there are atoms in 12 </span>grams<span> of </span>carbon-12<span> (</span>12<span>C), the </span>isotope<span> of </span>carbon<span> with </span>relative atomic mass<span> 12 by definition.
so to solve the moles, divide the mass with molar mass
moles = 4177 g / </span><span>133.34 g/mol
moles = 31.33 moles</span>
massive livand that sarah or someone is how u do it
