Once you have identified the limiting reactant, you calculate how much of the other reactant it must have reacted with and subtract from the original amount.
1. 100N to the right
2. 10N to the left
3. 0N they are balanced
4. 0N they are balanced
To calculate how many photons are in a certain amount of energy (joules) we need to know how much energy is in one photon.
Start by using two equations:
Energy of a photon = Frequency * Planck's constant (6.626 * 10^(-34) J-s)
Speed of light (constant 3 * 10^8 m/s) = Frequency * Wavelength
Which means:
frequency = Speed of Light / Wavelength
So energy of a photon = (Speed of light * Planck's constant)/(Wavelength)
You may have seen this equation as E = hc/<span>λ</span>
We have a wavelength of 691 nm or 691 * 10^-9 meters
So we can plug in all of our knowns:
E = (6.626 * 10^(-34) J-s) * (3.00 * 10^8 m/s) / (691 * 10^-9 m) =
2.88 * 10^(-19) joules per photon
Now we have joules per photon, and the total number of joules (0.862 joules)
,so divide joules by joules per photon, and we have the number of photons:
0.862 J/ (2.88 * 10^(-19) J/photon) = 3.00 * 10^18 photons.
D is the answer. You cannot say that anyone is good at anything because it doesn't say that. And they were surveying the class of 2010
Answer:
1.4 g H₂O
Explanation:
In a reaction, the reactants are usually not present in exact <em>stoichiometric amounts</em>, that is, <em>in the proportions indicated by the balanced equation</em>. Frequently a large excess of one reactant is supplied to ensure that the more expensive reactant is completely converted to the desired product. Consequently, some reactant will be left over at the end of the reaction. T<em>he reactant used up first in a reaction</em> is called the <em>limiting reagent</em>, because <u>the maximum amount of product formed depends on how much of this reactant was originally present</u>. When this reactant is used up, no more product can be formed.
