Answer:
Low value for copper recovery
Explanation:
The percentage recovery is obtained from;
Percent recovery = amount of substance you actually collected / amount of substance you were supposed to collect × 100
Note that the fact that some of the copper nitrate solution splashed out of the beaker means that some amount copper has been lost from the system. This loss of copper leads to a lower value of copper recovered from solution.
Given that 1 mole contains 6.02x10^23 molecules, 3.0x10^23 is just around half a mole. Then we check the number of moles for each choice:
A. This is approximately half a mole, since the molar mass of Br2 is 159.8 g/mol.
B. He has a molar mass around 4 g/mol, so this is 1 mole.
C. H2 has a molar mass of 2.02 g/mol, so this is 2 moles.
D. Li has a molar mass of around 6.97 g/mol, so this is around 2 moles.
Therefore the only choice that fits is A. 80 g of Br2.
C- more than one light year or B-exactly one light year
Answer:
2M
Explanation:
M=mol/L
1. Find moles of CoCl2
mass of substance/molar mass = 130/129.833 = 1.001 mol
3. Substitute in molarity equation
M=(1.001/0.5)
M= around 2M