Answer:
C. pieces of hair found at the crime scene.
Explanation:
using the pieces of hair, you can get the DNA of the person. This will give u a better lead in solving the crime.
Hope it helps u ....
Answer:
A. Reference blank
B. Cuvettes
C. Transmittance
D. Absorbance
E. Wavelength
Explanation:
A reference blank is a sample prepared using the solvent and any other chemicals in the sample solutions, but not the absorbing substance.
A square-shaped container, typically made of quartz, designed to hold samples in a spectrophotometer is known as Cuvettes.
A measurement of the amount of light that passes through a sample or percentage of light transmitted by the sample, with the respective intensities of the incident and transmitted beams is called Transmittance.
The measurement of the amount of light taken in by a sample is known as Absorbance
The wavelength is also the distance travelled by the wave during a period of oscillation. In spectrophotometry, the unit is inversely proportional to energy and commonly measured in nanometers
Answer:
4.00 moles
Explanation:
Avogadro´s number is 6.022 x 10²³ molecules, atoms, particles, etc.
Here we are talking of atoms of copper, so 1 mol of copper is equal to 6.022 x 10²³ atoms, and we only need to setup the proportion to find the number of mol in 2.41 x 10²⁴ atoms. ( Think of it like a dozen, avogadro´s is 6.022 x 10²³ )
( 1 mol copper/ 6.022 x 10²³ atoms of copper ) x 2.41 x 10²⁴ atoms
= 4.00 moles
The answer is Metallic bonds involve many valence electrons shared by many atoms, so the bonds can move around as the metal is pounded. The metallic bond structure of lead forms a cubic crystal structure and the atoms can roll over one another without breaking the metallic bonds. This is especially because the p orbital electrons of lead can be delocalized and the electrons can be shared with other lead ions in the cubic structure of lead.
[OH⁻] = 1.6 × 10⁻⁸ mol / dm³
<h3>Explanation</h3>
By definition, ![[\text{H}^{+}] = 10^{-\text{pH}}](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D%20%3D%2010%5E%7B-%5Ctext%7BpH%7D%7D)
, where ![[\text{H}^{+}]](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D)
is the concentration of proton in the solution.
pH = 6.2 for this solution. As a result, 
.
![[\text{H}^{+}] \cdot [\text{OH}^{-}] = \text{K}_w](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D%20%5Ccdot%20%5B%5Ctext%7BOH%7D%5E%7B-%7D%5D%20%3D%20%5Ctext%7BK%7D_w)
, where ![[\text{OH}^{-}]](https://tex.z-dn.net/?f=%5B%5Ctext%7BOH%7D%5E%7B-%7D%5D)
the concentration of hydroxide ions and 
is the dissociation constant of water.
at 0.10 MPa and 25 °C. As a result, ![[\text{OH}^{-}] = \text{K}_w / [\text{H}^{+}] = 10^{14} / (6.31 \times 10^{-7}) = 1.6 \times 10^{-8} \; \text{mol}\cdot \text{dm}^{-3}](https://tex.z-dn.net/?f=%5B%5Ctext%7BOH%7D%5E%7B-%7D%5D%20%3D%20%5Ctext%7BK%7D_w%20%2F%20%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D%20%3D%2010%5E%7B14%7D%20%2F%20%286.31%20%5Ctimes%2010%5E%7B-7%7D%29%20%3D%201.6%20%5Ctimes%2010%5E%7B-8%7D%20%5C%3B%20%5Ctext%7Bmol%7D%5Ccdot%20%5Ctext%7Bdm%7D%5E%7B-3%7D)
.
