Atomic mass Calcium = 40.078 a.m.u
40.078 g ---------------- 6.02x10²³ atoms
165 g -------------------- ??
165 x ( 6.02x10²³) / 40.078 => 2.47x10²⁴ atoms
hope this helps!
Explanation:
Rutherford conducted an experiment in which he took a thin gold particle film on which he passes alpha- particles. He noticed that:
- Most of the alpha particles get through the film and can be detected by the detector.
- Around small portion of the alpha particle deflected at small angles.
- A very very few alpha particle (approximately 1 out of 1 million alpha particles) just retraced their path which means come back from the center.
He concluded that:
<u>Most of the space of the atom is empty and in the center of the atom , there is solid mass which is the cause of the alpha particles to come back. He gave the term nucleus to this solid mass.</u>
Answer:
0.21 M. (2 sig. fig.)
Explanation:
The molarity of a solution is the number of moles of the solute in each liter of the solution. The unit for molarity is M. One M equals to one mole per liter.
How many moles of NaOH in the original solution?
,
where
is the number of moles of the solute in the solution.
is the concentration of the solution. 
for the initial solution.
is the volume of the solution. For the initial solution, 
for the initial solution.
.
What's the concentration of the diluted solution?
.
- is the number of solute in the solution. Diluting the solution does not influence the value of .
for the diluted solution. - Volume of the diluted solution:
.
Concentration of the diluted solution:
.
The least significant number in the question comes with 2 sig. fig. Keep more sig. fig. than that in calculations but round the final result to 2 sig. fig. Hence the result: 0.021 M.
Answer:
Explanatio(3) Atomic masses are a weighted average of the naturally occurring isotopes.
(3) Atomic masses are a weighted average of the naturally occurring isotopes. is the best statement for why most atomic masses on the Periodic Table are decimal numbers.
