The equation is:
3 O₂ + 4 Co → 2 Co₂O₃
Oxidation half reaction:
Co → Co³⁺ + 3 e
Reduction half reaction:
O₂ + 4 e → 2 O²⁻
To balance the equation number of electrons lost must be equal to number or electrons gained so we must multiply oxidation half time 4 and reduction half times 3
Answer: 40.1%
Explanation: The mass of calcium in this compound is equal to 40.1 grams because there's one atom of calcium present and calcium has an atomic mass of 40.1 . The molar mass of the compound is 100.1 grams. Using the handy equation above, we get: Mass percent = 40.1 g Ca⁄100.1 g CaCO3 × 100% = 40.1% Ca.
Given the volume of HCl solution = 30.00 mL
Molarity of HCl solution = 0.1000 M
Molarity, moles and volume are related by the equation:
Molarity = 
Converting volume of HCl from mL to L:
Calculating moles of HCl from volume in L and molarity:
The final moles would be reported to 4 sig figs. So the correct answer will be 0.03000 mol HCl
Correct option: C. 0.03000mol
Answer:
Extensive or inextinsive and either physical or chemical
Considering ideal gas behavior, the volume of 1 mol of gas at STP is 22.4 L; then the volume occupied by 1.9 moles is 1.9mol*22.4L/mol
The answer is 43 L if I am correct.
