Answer: law of conservation of matter states that mass in an isolated system can neither be created nor destroyed by chemical reactions or physical transformation.
thus, the mass of the reactants in a reaction must be equal to the mass of the products
Expression for the Balmer series to find the wavelength of the spectral line is as follows:
1 / λ = R

Where, λ is wavelength, R is Rydberg constant, and n is integral value (4 here → Fourth level)
Substitute 1.097 x 10⁷ m⁻¹ for R and 4 for n in the above equation
1 / λ = (1.097 x 10⁷ m⁻¹)
= 0.20568 x 10⁷ m⁻¹
λ = 4.86 x 10⁻⁷ m
since 1 m = 10⁹ nm
λ = 486 nm
A.how many moles of aspirin are in one tablet
0.325 g ( 1 mol / 180.2 g ) = 1.80 x 10^-3 mol
B. How many moles of oxygen are in one tablet of aspirin
1.80 x 10^-3 mol C9H8O4 ( 4 mol O / 1 mol <span>C9H8O4) = 7.21 x 10^-3 mol O
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C. How many atoms of carbon are in one tablet of aspirin
1.80 x 10^-3 mol C9H8O4 ( 9 mol C / 1 mol C9H8O4 ) ( 6.022 x 10^23 atoms C / 1 mol C ) = 9.76 x 10^21 atoms C
D. How many grams of oxygen in one tablet of aspirin
7.21 x 10^-3 mol O ( 16 g / mol ) = 0.12 g O