Answer:
Explanation:
We're asked to calculate the number of atoms of
Ca
in
153
g Ca
.
What we must first do is convert the given mass of calcium to moles of calcium, using its molar mass (referring to a periodic table, this is
40.08
g
mol
):
153
g Ca
(
1
mol Ca
40.08
g Ca
)
=
3.82
mol Ca
Using Avogadro's number,
6.022
×
10
23
particles
mol
, we can calculate the number of atoms present:
3.82
mol Ca
(
6.022
×
10
23
atoms Ca
1
mol Ca
)
=
2.30
×
10
24
atoms Ca
Answer:
The energy of a hydrogen atom's electron is determined by which principal quantum number n value corresponds to the energy state the electron occupies. where n=1,2,3,... is the quantum number that quantizes the energy levels. That is, they are discrete energy values proportional to 1n2 .
Explanation:
Answer:
Ocean Currents
Explanation:
The correct answer is Ocean currents.
When the earth receives solar radiation, a large fraction of this incident radiation is usually absorbed by the oceans and the seas, which become warm. Usually, equitorial regions are the ones that have this phenomenon. Now, when ocean currents are flowing from the equator, they usually carry this warm water with them thereby moving the greatest amount of heat from the equator on its way out.
For example, In the Pacific Ocean, there is a current known as Alaska Current that carries warm water in the northward direction thereby making Anchorage which is Alaska's largest city to have a much mild weather than the inland areas with the same latitude.
Answer:
3 element i.e carbon (C), hydrogen (H) and oxygen.
Explanation:
The following data were obtained from the question:
Subtance >>>>>>>> Chemical Formula
Glucose >>>>>>>>> C₆H₁₂O₆
Methane >>>>>>>> CH₄
Ethanol >>>>>>>>> C₂H₅OH
Hydrogen peroxide >> H₂O₂
From the above table, we can see that ethanol (C₂H₅OH) contains carbon (C), hydrogen (H) and oxygen
Therefore, the total number of elements present in ethanol, C₂H₅OH is 3.
Answer:
Explanation:
Given that:
The Half-life of 
= 
is less than that of 
Although we are not given any value about the present weight of .
So, consider the present weight in the percentage of to be y%
Then, the time elapsed to get the present weight of = 
Therefore;
here;
= Number of radioactive atoms relating to the weight of y of
Thus:
--- (1)
However, Suppose the time elapsed from the initial stage to arrive at the weight of the percentage of to be = 
Then:
---- (2)
here;
= Number of radioactive atoms of relating to 3.0 a/o weight
Now, equating equation (1) and (2) together, we have:
replacing the half-life of =
( since 
)
∴
The time elapsed signifies how long the isotopic abundance of 235U equal to 3.0 a/o
Thus, The time elapsed is
