The percentage of hydrogen in C7H18 is calculated as follows:
[18/(12*7+1*8)]*100=18%
The amount of hydrogen in 5.2moles is given by:(18/100)*5.2=0.94moles
A solution has an absorbance of 0.2 with a path length of 1 cm. Given the molar absorptivity coefficient is 59 cm⁻¹ M⁻¹, the molarity is 0.003 M.
<h3>What does Beer-Lambert law state?</h3>
The Beer-Lambert law states that for a given material sample, path length and concentration of the sample are directly proportional to the absorbance of the light.
A solution has an absorbance of 0.2 with a path length of 1 cm. Given the molar absorptivity coefficient is 59 cm⁻¹ M⁻¹, we can calculate the molarity of the solution using the following expression.
A = ε × b × c
c = A / ε × b
c = 0.2 / (59 cm⁻¹ M⁻¹) × 1 cm = 0.003 M
where,
- A is the absorbance.
- ε is the path length.
- b is the molar absorptivity coefficient.
- c is the molar concentration.
A solution has an absorbance of 0.2 with a path length of 1 cm. Given the molar absorptivity coefficient is 59 cm⁻¹ M⁻¹, the molarity is 0.003 M.
Learn more about the Beer-Lambert law here: brainly.com/question/12975133
Answer:
Protons: 2.
Electrons: 2.
Neutrons: 2.
Explanation:
Hello,
In this case, since an atom's atomic number is equal to the number of electrons, considering the electron configurations, taking into account that helium-4 is neither positively nor negatively charged, we can infer that the number of electrons equal the number of protons, which in this case are 2, due to the fact that is atomic number is 2.
Moreover, as helium-4's atomic number is 4 as a whole number, we compute the number of neutrons by using the shown below equation:

Regards.
Atomic mass is the mass of a chemical element expressed in atomic mass units. Molar mass the mass of a given substance divided by its amount of substance in (mol) .