2,8,1
It's in group 1, so its outershell only has 1 electron, and the other shells are completely filled, so 2 then 8. :)
Answer:
320 mmol
Explanation:
405.0 mL * 1L/1000 mL = 0.4050 L
0.79 M = 0.79 mol/L
0.79 mol/L * 0.4050 L=0.32 mol
0.32 mol * 10^3 mmol/1 mol = 320 mmol
Frequency = speed of light
---------------------------
wavelength
= 3 x 10^8
------------------------
344 x 10^-9
= 8.72 x 10^14 Hz.
Hope this helps!
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β− decay and β+ decay, which produce electrons and positrons respectively.