Answer:
The density of copper is 0.5 g/mL
Explanation:
Given data:
Mass of copper = 6 g
Volume of copper = 12 mL
Density of copper = ?
Solution:
Formula:
d = m/v
d = density
m = mass
v = volume
d = 6 g/ 12 mL
d = 0.5 g/mL
Thus, the density of copper is 0.5 g/mL
Answer:Answer: The step that is NOT necessary to complete before a cuvette is placed into the spectrophotometer is option B (Write, in ink, either sample or blank on the side of the cuvette to keep track of them)
Explanation: spectrophotometer is an instrument used to measure the light intensity absorbed after being passed through a solution. Before the absorbance of the sample solution, a solvent solution called blank is used for the calibration of the machine and this blank solvent is placed in a cuvette. The procedure usually comes first before the main sample is processed. Therefore there is no need to
Write, in ink, either sample or blank on the side of the cuvette to keep track of them. This is so since sample and blank is not absorbed at the same time by the machine.
Just find the energy of the <span>blueviolet light with a wavelength of 434.0 nm using the formula:
E = hc / lambda
E = energy
c= speed of light = 3 x 10^8 m/s
h = planck's constant = 6.6 x 10^{-34} m^2 kg / s
lambda = 434 nm = 434 x 10^{-9} m
Putting these values (with appropriate units) in the above formula :
we get: Energy, E = 4.5 x 10^{-19} J
E = 0.45 x 10^{-18} J
Now, the </span>minimum energy is 2.18×10^-{18} J but our energy is 0.45 x 10^{-18} J which is less.
<span>Means the electron will not be removed
</span>
Answer:
KOH and H₂SO₄
Explanation:
Neutralization reaction:
It is the reaction in which acid and base react with each other and produce salt and water.
For example:
2KOH + H₂SO₄ → K₂SO₄ + 2H₂O
1. Potassium hydroxide and sulfuric acid react to produce potassium sulfate salt and water.
2. Potassium hydroxide and phosphoric acid react to produce potassium phosphate and water.
H₃PO₄ + 3KOH → K₃PO₄ + 3H₂O
3. Phosphoric acid sodium hydroxide react to produce sodium phosphate and water.
H₃PO₄ + 3NaOH → Na₃PO₄ + 3H₂O