How many cu atoms are present in a piece of sterlingsilver jewelry weighing 33.24 g ? (sterling silver is a silver–copper alloy containing 92.5% ag by

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.

your answer is c) plasma

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answer: any goods being imported from another country may be subject to issued by the federal government are tariffs

explanation:  

tariffs are a tax on anything that are imported from abroad. government use them to protect and boost their local industries and the thought is that they encourage consumers to buy local instead of importing and they will hope will protect jobs and economy in the country that implements them