The validity of scientific theories and laws depends on evidence. Which of the following statements of evidence supports a law r
ather than a theory?
Electrons orbit the nucleus of an atom within a certain radius.
DNA analysis reveals that a modern species is related to an extinct species.
Seafloor spreading occurs at a rate of three centimeters per year in the mid-Atlantic.
The amount of matter in a closed system is the same at the start of a reaction as at the end of the reaction.
Electrons orbit the nucleus of an atom within a certain radius.
DNA analysis reveals that a modern species is related to an extinct species.
Seafloor spreading occurs at a rate of three centimeters per year in the mid-Atlantic.
The amount of matter in a closed system is the same at the start of a reaction as at the end of the reaction.
2 answers:
You might be interested in
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.