Answer:
It is liquid at most temperatures on Earth.
1) The time depends on what the lab wanted you to do. It will tell you in the procedure when you are supposed to considered a reaction to be complete and you just measure the time for that to happen.
2) Most text books say that increasing the concentration of one or more reactants will increase the rate of the reaction. To prove this with your data you need to show that when you increased the concentration of one of the reactants, the reaction rate did increase. The results of this experiment are not enough to make a general statement since the experiment was not on a large enough scale to diffidently prove anything. (you could have been testing the one exception or had a error in one of your trials)
I hope this helps. Let me know in the comments if anything is unclear.
(The concentration of one or more of the reactants will increase the rate of the reaction. This is explained through the fact that all reactions require collisions that have certain orientations and a minimum energy level. By increasing the concentration of one or more reactants, you increase the number of collisions which increases the rate since requires collisions in order to occur.) <span />
Answer:
349.503 g
https://www.convertunits.com/from/moles+Copper/to/grams
here is a link, you can convert moles of copper to grams here
Answer:
- <u>2.59 × 10⁻⁷ m = 259 nm</u>
Explanation:
You need to calculate the wavelength of a photon with an energy equal to 463 kJ/mol, which is the energy to break an oxygen-hydrogen atom.
The energy of a photon and its wavelength are related by the Planck - Einstein equation:
Where:
- h = Planck constant (6.626 × 10⁻³⁴ J . s) and
- ν = frequency of the photon.
And:
Where:
- c = speed of light (3.00 × 10⁸ m/s in vacuum)
- λ = wavelength of the photon
Thus, you can derive:
Solve for λ:
Before substituting the values, convert the energy, 463 kJ/ mol, to J/bond
- 463 kJ/ mol × 1,000 J/kJ × 1 mol / 6.022 × 10 ²³ atom × 1 bond / atom
= 7.69×10²³ J / bond
Substitute the values and use the energy of one bond:
- λ = 6.626 × 10⁻³⁴ J . s × 3.00 × 10⁸ m/s / 7.69×10²³ J = 2.59 × 10⁻⁷ m
The wavelength of light is usually shown in nanometers:
- 2.59 × 10⁻⁷ m × 10⁹ nm / m = 259 nm ← answer
Crystsals can precipitate out of solution when some of the solvent is evaporated. For example, if you have sodium chloride in solution and you evaporate out the water some sodium chloride crystals will form. I hope this helps. Let me know if anything is unclear.