Diphosphorus heptachloride
CaSO4 - to find the molar mass, you add the element's mass number.
40.08 + 32.06 + (16x4)
= 136.14
Any of the other alkali metals not mentioned (I.e. rubidium, caesium or francium). They are all group one metals meaning that they contain one valence (outer shell) electron so they will have similar properties. Francium is the most reactive alkali metal while lithium is the least reactive (if you’d like me to explain that let me know :) )
The relationship between energy of a single photon and its wavelength can be determined using the formula E=hc/lambda where E is energy, h is Planck's constant, c is the speed of light, and lambda is photons.
Before being able to solve for energy, need to convert nanometers to meters.
407 nm (1 m/1 x 10^9 nm) = 4.07 x 10^-7 m
Then plug in the values we know into the equation.
E h(Planck's constant) c(speed of light)
E = (6.63 x 10^-34 Js)(3 x 10^8 m/s) / 4.07 x 10^-7 m (lambda)
E=(0.000000000000000000000000000000000663js)(300,000,000m/s)=1.989×10^-25j/ms
E=1.989x10^-25j/ms /{divided by} 4.07x10^-7m = 4.8869779x10^-33 J (the meters cancel out)
E = 4.89 x 10^-33 J
This gives us the energy in Joules of a single photon. Now, we can find the number of photons in 0.897 J
0.897J / 4.89 x 10^-33 J = ((0.897 J) / 4.89) x ((10^(-33)) J) = 1.8343558 x 10^-34
1.83435583 × 10-34m4 kg2 / s4 photons