Answer:
2.74 M
Explanation:
Given data:
Mass of sodium chloride = 80.0 g
Volume of water = 500.0 mL
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Now we will convert the mL into L.
500.0 mL× 1 L /1000 mL = 0.5 L
In next step we will calculate the number of moles of sodium chloride.
Number of moles = mass/molar mass
Number of moles = 80.0 g/ 58.4 g/mol
Number of moles = 1.37 mol
Molarity:
M = 1.37 mol/ 0.5 L
M = 2.74 M
Do you have any pictures of your options
Answer:
The answer is True
Explanation:
The Ph of bady fluids have different ranges but it should be nearly constant to maintain the health of the human, The PH of the human blood is from 7.35 to 7.45 and the other blood fluids have different ranges . The PH shouldn't drop below 6.9 because it is so dangerous for human health and result coma. if there is high value of PH this indicates high numbers of OH- and low value of PH this indicates high numbers of H+
each organ has a certain PH value to do its function very well ,there is an organ needs acidic environment to work well and other organ needs an alkaline environment to do its work.
Answer:
0%
Explanation:
- The probability that both of the parents are homozygous recessive is zero.
- In our case, The gene for tallness is dominant over the gene for dwarfism
- Therefore; TT is homozygous dominant while tt is homozygous recessive and Tt is heterozygous.
- Heterozygous genotype (Tt) will exhibit a tall phenotype.
- When two parents are crossed and all the offsprings are tall then the possible genotype of the parents is either;
- Homozygous dominant for both parents or
TT x TT
2. One parent is homozygous dominant and the other is homozygous recessive.
TT x Tt
- Therefore, the probability of having both parents as homozygous recessive when all the offspring are tall is Zero.
Answer:
Explanation:
When an electron jumps from one energy level to a lower energy level some energy is released in the form of a photon.
The difference in energy between the two levels is the energy of the photon and that energy is related to the frequency of the photon by the Einstein - Planck equation:
Where,
- E = energy of the photon,
- h = 6.626×10⁻³⁴ J.s, Planck constant, and
- ν = frequency of the photon.
So, to find the frequency you must first find the energy.
The transition energy can be calculated using the formula:
Where E₀ = 13.6 eV ( 1 eV = 1.602×10⁻¹⁹ Joules) and n = 1,2,3,...
So, the transition energy between n = 4 and n = 3 will be:
- ΔE = - E₀ [ 1/4² - 1/3²] = - 13.6 eV [1/16 - 1/9] = 0.6611. . .eV
- ΔE = 1.602×10⁻¹⁹ Joules/eV × 0.6611... eV = 1.0591 ×10⁻¹⁹ Joules
Now you can use the Einstein - Planck equation:
- ν = 1.0591 ×10⁻¹⁹ J / 6.626×10⁻³⁴ J.s = 1.60×10¹⁴ s⁻¹ (rounded to 3 significant figures).
