I believe it would be the first option. It forms iron oxide (rust) when exposed to moisture and air.
Answer:
Element Atomic Number Atomic Mass
Nickel 27 58.6934
Cobalt 28 58.9332
Copper 29 63.546
Zinc 30 65.39
Explanation:
Solution with a pH of 3 has 10⁻³ moles of H⁺, solution with a pH of 4 has 10⁻⁴ moles of H⁺ and solution with a pH of 5 has 10⁻⁵ moles of H⁺ (in dm³) so the solution with a pH of 3 has 10 times more H⁺ ions than the solution with a pH of 4 and 100 times more H⁺ ions than the solution with a pH of 5.
Magma that cools quickly forms one kind of igneous rock, and magma that cools slowly forms another kind. When magma rise from deep within the earth and explodes out of a volcano, it is called lava, and it cools quickly on the surface. Rock formed in this way is called extrusive igneous rock.
The molar mass of CuCl2 is 134.45 g/mol; therefore, you divide 2.5 g of CuCl2 by 134.45 g of CuCl2 leaving you with 0.019 moles
