Question in incomplete, complete question is:
Technetium (Tc; Z = 43) is a synthetic element used as a radioactive tracer in medical studies. A Tc atom emits a beta particle (electron) with a kinetic energy (Ek) of 
. What is the de Broglie wavelength of this electron (Ek = ½mv²)?
Answer:
is the de Broglie wavelength of this electron.
Explanation:
To calculate the wavelength of a particle, we use the equation given by De-Broglie's wavelength, which is:
where,
= De-Broglie's wavelength = ?
h = Planck's constant = 
m = mass of beta particle = 
= kinetic energy of the particle =
Putting values in above equation, we get:
is the de Broglie wavelength of this electron.
I think it’s 20 mol
Sorry if I’m wrong
Answer:
Explanation:
<u>First mixture</u>:
40 wt% methanol - 60 wt% water 200 kg
<u>Second mixture</u>:
70 wt% methanol - 30 wt% water 150 kg
Final mixture:
If, the compositions are constant, the only variables are the mass of each mixture used in the final one, so there can be only one independent balance.
Answer: The standard free energy change for a reaction in an electrolytic cell is always positive.
Explanation:
Electrolytic cells use electric currents to drive a non-spontaneous reaction forward.
Relation of standard free energy change and emf of cell
where,
= standard free energy change
n= no of electrons gained or lost
F= faraday's constant
= standard emf
= standard emf = -ve , for non spontaneous reaction
Thus 
Thus standard free energy change for a reaction in an electrolytic cell is always positive.
Answer:
you divide 71.5 by 2
Explanation:
it's may look intimidating but the question is actually really simple.
