solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 
invisable
you probably dont want to put that...
When the balanced reaction equation is:
2HCl(aq) + Ca(OH)2(aq) → CaCl2(aq) + 2H2O(l)
from the balanced equation, we can get the molar ratio between HCl & Ca(OH)2
2:1
∴ the volume of Ca(OH)2 = 15.8 L HCl * 1.51 m HCl * (1mol Ca(OH)2/ 2mol HCl) * (1L ca(OH)2/0.585 mol Ca(OH)2
= 20.4 L
Answer:
Oxygen is in excess.
Explanation:
The coefficients of the balanced equation create a mole ratio that shows the ratio of how many reactants are used up and products are created.
The mole ratio of Mg to O2 in this equation is 2:1, which means that for every two moles of Mg used, there will be 1 mole of O2 used.
If we have 3.00 moles of Mg, we will only need 1.5 moles of oxygen to completely burn the Mg. Therefore, when all 3.00 moles of Mg are used, there will still be some of the 2.20 moles of oxygen remaining.
