The percent composition of each element can be calculated as follows:
% composition = (mass of element / total mass) * 100
The total mass of the quarter is given to be 5.670 grams
Mass of Cu = 5.198 grams
Mass of Ni = 0.472 grams
Substitute in the above equation to get the mass percentage of each element as follows:
% of Cu = (5.198/5.670) * 100 = 91.675%
% of Ni = (0.472/5.670) * 100 = 8.325%
Answer:
Oxidation number of F2O = 0−(−1×2)
State of oxygen will be=+2
1023 molecules or atoms depending on substance
Answer:
Explanation: A yellow precipitate o lead iodide is formed. see equation of reaction below: 
→ 
Th PbI2 is the insoluble yellow precipitate
Qualitative because it changed its colour not its quantity :)
