If the incoming photon had a frequency of 2.0 e14 hz, would you have a photo-electron ejected?

yes

Explanation:

The frequency of incident radiation is given as [f] = Hz

The energy of the photon will be calculated as -

                                         E= hf

                                           =

                                           =

We have = 1 ev.

The photo electric emission is dependent on the work function of the metal.

If light of suitable frequency i.e the energy of incident radiation is greater than or equal to work function will incident on the metal surface, the electrons will be emitted from the surface barrier of the metal.

Hence, from the above calculated value, if the work function of a metal is less than 0.828ev, then electron emission will be possible.

Normally metals have a work function greater than 1 ev. So, for most of the metals, the electron will not be emitted. But for some alkali metals under suitable condition, the work function is less than 0.8 ev. The electron emission will be possible for these substances.

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )