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:
5.83 g
Explanation:
First, you must start with a balanced equation so you can see the mole ratios.
NaOH + H₃BO₃ --> NaBO₂ + 2H₂O
You can see that it takes 1 mole of sodium hydroxide to form 1 mole of sodium borate. 1:1 ratio
Now you must calculate how many moles of NaOH 35.47 g equals.
Na = 22.99 amu
O = 15.99 amu
H = 1.008 amu
NaOH = 39.997 amu
35.47 g ÷ 39.997 amu = 0.08868 moles of NaOH
Since it's a 1:1 ratio, the same number of moles of NaBO₂ is created. Now you must convert moles to grams.
Na = 22.9 amu
B = 10.81 amu
2 O = 31.998 amu
NaBO₂ = 65.798 amu
0.08868 moles x 65.798 = 5.83 g
Answer:
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Explanation:
Inertia increases as an object's <u>Mass</u> increases.
Answer:
A fluorine atom has nine protons and nine electrons, so it is electrically neutral. If a fluorine atom gains an electron, it becomes a fluoride ion with an electric charge of -1.
Answer:
A.All Mixtures Are Made Up Of Solutions
Explanation: