Answer:
D 2,2
Explanation:
We can see that there are 2 chlorines on the reactant side so there has to be a 2 on the product side
Now we have Na + Cl2 --> 2NaCl
The problem now is that there are 2 sodiums on the product side so add a 2 to the Na on the reactant side
2Na + Cl2 --> 2NaCl
Now it's balanced!
How does the Sun get energy?
Answer:
Nuclear fushion
Explanation:
The sun generates energy from a process called nuclear fusion. During nuclear fusion, the high pressure and temperature in the sun's core cause nuclei to separate from their electrons
The blue colour of the sky results from the scattering of sunlight by air molecules. Blue light has a frequency if about 7.5*10^14Hz
Calculate the energy of a mole of photon associated with this frequency
Answer: The energy of a mole of photon associated with this frequency is [tex]49.5\times 10^{-20}J[/tex]
Explanation:
The energy and frequency are related by :
[tex]E=N\times h\times \nu[/tex]
E = energy of photon
N = number of moles = 1
h = planks constant = [tex]6.6\times 10^{-34}Js[/tex]
[tex]\nu[/tex] = frequency = [tex]7.5\times 10^{14}Hz[/tex]
[tex]E=1\times 6.6\times 10^{-34}Js\times 7.5\times 10^{14}s^{-1}=49.5\times 10^{-20}J[/tex]
The energy of a mole of photon associated with this frequency is [tex]49.5\times 10^{-20}J[/tex]