B because....................
Answer:
Explanation:
1 mol of sodium = 23 grams (use the number on your periodic table).
0.7350 mol sodium = x
Cross multiply
1*x = 0.7350 * 23
x = 16.905
You will get slightly less than this, depending on your periodic table. But the method will be the same.
Answer:
1.8 × 10² s
Explanation:
Let's consider the reduction that occurs upon the electroplating of copper.
Cu²⁺(aq) + 2 e⁻ ⇒ Cu(s)
We will establish the following relationships:
- 1 g = 1,000 mg
- The molar mass of Cu is 63.55 g/mol
- When 1 mole of Cu is deposited, 2 moles of electrons circulate.
- The charge of 1 mole of electrons is 96,486 C (Faraday's constant).
- 1 A = 1 C/s
The time that it would take for 336 mg of copper to be plated at a current of 5.6 A is:

(D) exposure of a photographic plate