Answer:
Element symbol: Kr.
Mass number: 77.
Charge : 0.
Explanation:
Hello,
In this case, since such substance has the same amount of protons and electrons we can infer it is an atom whose number of neutrons is defined by considering its atomic mass or mass number and atomic number which is actually equal to the number of protons and electrons (36):
In such a way, solving for the atomic mass we obtain:
It means that the element is krypton (Kr) as it has 36 electrons and protons so its charge is 0.
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Answer:
0.675 atm
513 Torr
Explanation:
Given is that, the atmospheric pressure on the surface of Venus is
6.84 X 10⁴ Pa.
1 atm (atmospheric pressure) is equal to 101325 pascal (Pa).
To convert divide the pressure value by 101325.
Pressure in atm =
= 0.675055 atm
Rounding it off to 3 significant digits: 0.675 atm
Now, one Torr is 133.322 Pa. For conversion, divide the pressure value by 133.322.
Pressure in Torr =
=513.04219 Torr
Rounding it off to 3 significant digits: 513 Torr
Rate law for the given 2nd order reaction is:
Rate = k[a]2
Given data:
rate constant k = 0.150 m-1s-1
initial concentration, [a] = 0.250 M
reaction time, t = 5.00 min = 5.00 min * 60 s/s = 300 s
To determine:
Concentration at time t = 300 s i.e.
Calculations:
The second order rate equation is:
substituting for k,t and [a] we get:
1/[a]t = 0.150 M-1s-1 * 300 s + 1/[0.250]M
1/[a]t = 49 M-1
[a]t = 1/49 M-1 = 0.0204 M
Hence the concentration of 'a' after t = 5min is 0.020 M