The mass of piece of sterling silver jewelry is 33.24 g. It contains 92.5% silver Ag by mass. Since, sterling silver is an alloy of Ag-Cu thus, percentage of Cu will be:
% Cu=100-92.5=7.5%
Thus, mass of copper will be:
Molar mass of Cu is 63.546 g/mol, thus, number of moles of Cu can be calculated as follows:
Here, m is mass and M is molar mass.
Putting the values,
Now, in 1 mole of Cu there are 
thus, in 0.03923 mol, number of Cu atoms will be:
Thus, number of atoms of Cu will be
.
Answer:
CH₅N
Explanation:
In the combustion, all of the C in the compound was used to produce CO₂ in a 1:1 ratio. Thus, the moles of CO₂ (MW 44.01 g/mol) produced equals the moles of C in the compound:
(44.0 g)(mol/44.01g) = 0.99977 mol CO₂ = 0.99977... mol C
Similarly, all of the H in the compound was used to produce H₂O in a ratio of 2H:1H₂O. The moles of H₂O (MW 18.02 g/mol) produced was:
(45.0 g)(mol/18.02g) = 2.497...mol H₂O
Moles of H is found using the molar ratio of 2H:1H₂O:
(2.497...mol H₂O)(2H/1H₂O) = 4.994...mol H
The ratio of H to C in the compound is:
(4.994...mol H)/(0.99977... mol C) = 5 H:C
Some NO₂ was produced from the N in the compound. Assuming a 1:1 ratio of C:N, the simplest empirical formula is: CH₅N.
Answer:2NaF is the correct one. It’s a simple combination and can be be split with relative ease
Explanation:
Answer:
Science is the study of the physical or material world. Science is important because it can answer questions about new ideas and can advance technologies
Explanation:
