I believe the first space is 1. alloys, and the second space is also 1. main. I don't know for sure but I hope this helps.
Answer:
The correct answer is option b. "He passed cathode rays through a magnetic field and measured the deflection".
Explanation:
J. J. Thomson was a notorious scientist that did not only made the discovery of the electron, but he measure its charge to mass ratio. In order to determine this property, Thomson passed cathode rays through a magnetic field and measured the deflection. Cathode rays are actually composed of particles, which are now known as electrons, and its charge to mass ratio is about 10^8 coulomb per gram.
Answer:

Explanation:
Hello,
In this case, for the given molarity and volume of such solution, the moles of sodium sulfate are computed below:

Now, by using the Avogadro's number, the ions result:

Best regards.
Answer:
3.8 x 10²⁴molecules
Explanation:
Given parameters:
Number of moles = 6.32moles
Unknown:
Number of molecules = ?
Solution:
The number of moles can be used to derive the number of molecules found within a substance.
Now,
1 mole of substance contains 6.02 x 10²³ molecules
6.32 mole of PBr₃ will contain 6.32 x 6.02 x 10²³ = 3.8 x 10²⁴molecules