Number of proton K=19
so, 42 - 19 =23
then the answer in 19 protons and 23 neutrons
The answer to your question is nitrogen dioxide
Answer:
n = 0.573mol
Explanation:
PV = nRT => n = PV/RT
P = 1.5atm
V = 8.56L
R = 0.08206Latm/molK
T = 0°C = 273K
n = (1.5atm)(8.56L)/(0.08206Latm/molK)(273K) = 0.573mol
Answer:
67.6 years is the time the isotope take to decay from 0.900g to 0.170g
Explanation:
The radioactive decay follows first order law:
Ln [A] = -kt + ln[A]₀
<em>Where [A] is concentration after time t,</em>
<em>k is decay constant:</em>
<em>k = ln 2 / t(1/2)</em>
<em>k = ln2 / 28.1 years</em>
<em>k = 0.02467 years⁻¹</em>
<em>[A]₀ = Initial concentration.</em>
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We can replace concentration and use the mass of the isotope:
Ln [A] = -kt + ln[A]₀
Ln [0.170g] = -0.02467 years⁻¹t + ln[0.900g]
-1.667 = -0.02467 years⁻¹t
t =
<h3>67.6 years is the time the isotope take to decay from 0.900g to 0.170g</h3>