The number 4012 has how many significant figures?
1 answer:
You might be interested in
Answer:
See explanation.
Explanation:
Hello,
In this case, we can show how the empirical formula is found by following the shown below procedure:
1. Compute the moles of carbon in carbon dioxide as the only source of carbon at the products:
2. Compute the moles of hydrogen in water as the only source of hydrogen at the products:
3. Compute the mass of oxygen by subtracting the mass of both carbon and hydrogen from the 0.4647-g sample:
4. Compute the moles of oxygen by using its molar mass:
5. Divide the moles of carbon, hydrogen and oxygen by the moles of oxygen (smallest one) to find the subscripts in the empirical formula:
6. Search for the closest whole number (in this case multiply by 2):
Moreover, the empirical formula suggests this compound could be carboxylic acid since it has two oxygen atoms, nevertheless, this is not true since the molar mass is 222.27 g/mol, therefore, we should compute the molar mass of the empirical formula, that is:
Which is about three times in the molecular formula, for that reason, the actual formula is:
It suggest that the compound has a highly oxidizing character due to the presence of oxygen, therefore, we cannot predict the distribution of the functional groups as it could contain, carboxyl, carbonyl, hydroxyl or even peroxi.
Best regards.
Number of moles is defined as the ratio of given mass in g to the molar mass.
The mathematical formula is:
Number of moles = (1)
Number of zinc atoms is equal to , by Avogadro number, number of moles can be calculated.
As, 1 mol= atoms, hence,
= 0.2822 mol
Now, from formula (1), calculate mass in g (molar mass of zinc = 65.4 g/mol)
0.2822 mol =
mass in g =
= 18.45588 g
Thus, by rounding off the above number, it will come near about 19 g approximately.
Hence, option (C) is the correct answer.