B don’t know what light has to do with a ball bouncing
Answer:
pH = 9.25
Explanation:
Reaction of ammonia (NH₃) with hydrochloric acid (HCl) is:
NH₃ + HCl → NH₄⁺ + Cl⁻
As equal volumes of a 0.020M solution of NH₃ and a 0.010M solution of react, molarity of NH₃ after reaction is 0.010M and 0.010M of NH₄⁺.
For the buffer NH₄⁺/NH₃ H-H equation to find pH of solution is:
pH = pKa + log₁₀ [NH₃] / [NH₄⁺]
pH = 9.25 + log₁₀ [0.010M] / [0.010M]
<em>pH = 9.25</em>
Answer:
group VI
Explanation:
there are 6 valance electrons and since valance electrons = group number, the group number will be 6
Answer:
There are
moles of bactoX present in a 3.0 μL sample volume that contains 7.512×106 bacterial cells
Explanation:
Given that:
The number of molecules present in one bacterial cell is
molecules
and the sample contains
molecules.
Number of moles = number of molecules /Avogadro's number
where;
Avogadro's number = 6.023 × 10²³
Number of moles = ![\dfrac{7.140 \times 10^3}{6.023 \times 10^{23}}](https://tex.z-dn.net/?f=%5Cdfrac%7B7.140%20%5Ctimes%2010%5E3%7D%7B6.023%20%5Ctimes%2010%5E%7B23%7D%7D)
Number of moles =
moles
So;
moles is present in one bacteria cell
Similarly; the sample contains
molecules.
Therefore; the number of moles present in the bactoX is = ![1.185 \times 10^{-20} \times 7.512 \times 10^6](https://tex.z-dn.net/?f=1.185%20%5Ctimes%2010%5E%7B-20%7D%20%5Ctimes%207.512%20%5Ctimes%2010%5E6)
=
moles
Answer:
Xenon
Explanation:
Avogadro’s number represent the number of the constituent particles which are present in one mole of the substance. It is named after scientist Amedeo Avogadro and is denoted by
.
Avogadro constant:-
![N_a=6.023\times 10^{23}](https://tex.z-dn.net/?f=N_a%3D6.023%5Ctimes%2010%5E%7B23%7D)
Let the molar mass of the element is x g/mol
So,
atoms have a mass of x g
Also,
atoms have a mass of
g
This mass is equal to 848 g
So,
![\frac{x}{6.023\times 10^{23}}\times 3.89\times 10^{24}=848](https://tex.z-dn.net/?f=%5Cfrac%7Bx%7D%7B6.023%5Ctimes%2010%5E%7B23%7D%7D%5Ctimes%203.89%5Ctimes%2010%5E%7B24%7D%3D848)
x= 131.3 g/mol
This mass correspond to xenon.