Answer:
No
Explanation:
No. The demonstration in question does not infringe upon the conservation of mass.
The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction; however, mass can change from one form to another during the process.
In this instance, although the remnants of the paper weigh 0.5 g compared to the original weight of 2.5 g, the ashes and gases produced during combustion account for the missing mass of the paper.
The portion that has been burnt has transformed into other states. If the gas and ashes are adequately contained, they will correspond to the weight of the original paper when added to the remaining paper.
The isotopic mass of 47Z is calculated to be 46.96 amu. Isotopes of a single element differ in neutron count, and to ascertain the relative atomic mass, we consider each isotope's mass weighted by their natural abundance. This provided a computation to derive the mass of 47Z.
Solution:
The molecular formula is PbSO₄, indicating lead sulfate
Option c.
Explanation:
The percentage makeup shows that in 100 g of this compound, there are:
68.3 g of Pb, 10.6 g of S, and (100 - 68.3 - 10.6) = 21.1 g of O
To find the moles of each element, we divide by their molar masses:
68.3 g Pb / 207.2 g/mol = 0.329 moles Pb
10.6 g S / 32.06 g/mol = 0.331 moles S
21.1 g O / 16 g/mol = 1.32 moles O
Next, we find the mole ratio by dividing each by the smallest number of moles:
0.329 / 0.329 = 1 Pb
0.331 / 0.329 = 1 S
1.32 / 0.329 = 4 O
Thus, the molecular formula is PbSO₄, representing lead sulfate.
