11. (2 pts) A photon with energy 44.8 eV is absorbed by a hydrogen atom in its ground state, knocking the electron out. What is the speed of the electron as it leaves?

3.3·10^6 m/s

Explanation: Ionization energy of H is 13.6 eV. So the kinetic energy of electron is 31,2 eV.  Kinetic Energy of Electron is  E = ½mv^2

1 eV = 1.60·10^-19 J and  m = 9.1·10^-31 kg.   Solving speed v = √( 2E / m)

v = √(2·31.2·1.60·10^-19 J /9.1·10^-31 kg) = 3.3·10^6 m/s

  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