Question

You have a pure (24-karat) gold ring with mass Gold has an atomic mass of and an atomic number of 79. (a) How many protons are in the ring, and what is their total positive charge? (b) If the ring carries no net charge, how many electrons are in it?

Answer 1

Answer:

Explanation:

(a)

Gold has an atomic mass of 197 g/mol means 197 g of gold contains 6.023×10^{-23} atoms.

therefore number of atoms in 17.4 g is

$n= \frac{6.23\times10^{23}\times17.4}{197}$

$5.32\times10^{22}$

Number of protons in each atom is 79.

therefore Total number of protons is 5.32×10^{22}×79 =4.2×10^24. protons

Their total positive charge is 4.2×10^{24}×1.6×10^{-19) =6.72×10^5 C.

(b)

equal number of protons should be there to neutralize the material therefore number of electrons is 4.2×10^(24.)