Answer:
The net charge of 1.3 g nugget of pure gold after 1.68% of its electrons are removed is 559 C
Step-by-step explanation:
When an atom gains electrons it becomes negatively charged. Conversely, when it looses electrons the atoms becomes positively charged thus
To solve this question, we rely on the relationship between the nmber of particles present in a given mass of an atom, Avogadro's number and number of moles, n
The given variables are
mass of pure gold nugget = 1.30 g
Quantity of electrons removed = 1.68% of electrons present in the gold sample
Molar mass of gold = 197 g/mol
Avogadro's number = 6.02 × 10²³ atoms/mole
qc = one electron charge = -1.06 × 10⁻¹⁹ C/electron
Electrical charge of gold nugget = 0 C
Number of electrons in one gold atom = 79 electrons
Solving for the number of prticles or gold atoms in 1.3 grams of gold we get
n mass/(molar mass) = 1.3/197 moles of gold = 0.0066 moles
number of particles in 0.0066 moles of gold N = n×
= 0.0066 × 6.02 × 10²³ = 3.97 × 10²¹ atoms
since 79 electrons are present per particle we have
3.97 × 10²¹ × 79 = 3.14 × 10²³ electrons
quantity of elecrtrons removed = 1.68% of 3.14 × 10²³ electrons =1.68/100 × 3.14 × 10²³ electrons = 0.0168 × 3.14 × 10²³ electrons = 5.3 × 10²¹ electrons
The net charge of 5.3 × 10²¹ electrons = 5.3 × 10²¹ electrons × -1.06 × 10⁻¹⁹ C/electron =
5.59 × 10² C = 559 C