Answer:
The correct answer is the imperial system.
Explanation:
Only three countries in the world, that is, the United States, Myanmar, and Liberia use the imperial system. These include measurements in the form of inches, ounces, Fahrenheit, and feet. In the imperial system, the distances, height, weight, or area measurements are used eventually that traced back to everyday items or parts of the body.
In comparison to other metric systems, the units used in the imperial system are not further differentiated easily into parts of hundreds or thousands, and are thus, regarded of less use in comparison to other metric systems by some. The real follower of the imperial system at present in the world is the United States.
Answer:
Pentacarbon heptasilicide.
Explanation:
In order to name the following compound, we need to identify whether it is molecular or ionic.
Molecular compounds consist of non-metal atoms, while ionic compounds would have metal cations in their composition.
In the given compound, 
, we have two non-metals, carbon and silicon, meaning we should follow the molecular compound naming rules. The rules involve using prefixes to state the number of individual atoms.
The two prefixes required here are 'penta' for 'five' to indicate 5 carbon atoms present and 'hepta' for 'seven' to indicate 7 silicon atoms present.
The first part of the name would be pentacarbon (notice that the standard name for the first element is used). The second part would be heptasilicide (notice that the second atom would have an ending of -ide followed by the standard beginning of silicon).
As per the given chemical formula- Na2CO3.10H2O, one mole of the chemical compound contains 13 moles of oxygen atoms. Hence
Number of moles of oxygen atoms in one mole of Na2CO3.10H2O = 13
number of moles of oxygen atoms in 0.2 moles of Na2CO3.10H2O = 13 X 0.2 = 2.6
Now, one mole of a substance contains 6.022 X 10^23 particles of the substance. Thus
number of atoms of oxygen in one mole of oxygen atom = 6.022 X 10^23
number of moles of oxygen atoms in 2.6 moles of oxygen atoms = 2.6 X 6.022 X 10^23 = 15.657 X 10^23
= 1.566 X 10^24
Thus, there are 1.566 X 10^24 atoms of oxygen in 0.2 moles of Na2CO3.10H2O.
4.7
Particles as small as atoms exist.
