Question

there are ________ hydrogen atoms in 25 molecules of c4h4s2. 1.5 × 10^25 6.0 × 10^25 100 25 3.8 × 10^24 question 9 1 pts what is the empirical formula of a compound that contains 29% na, 41% s, and 30% o by mass? na2s2o3 naso3 naso na2s2o6 naso2

Explanation:

Step1: Analyze the molecular formula

In one molecule of \(C_4H_4S_2\), there are 4 hydrogen atoms.

Step2: Calculate the number of hydrogen atoms

If there are 25 molecules of \(C_4H_4S_2\), then the number of hydrogen atoms is \(25\times4 = 100\).

Step1: Assume 100g of the compound

If we assume 100g of the compound, then the mass of \(Na = 29g\), mass of \(S=41g\), mass of \(O = 30g\).

Step2: Calculate the number of moles

The molar mass of \(Na\) is \(M_{Na}=22.99g/mol\), moles of \(Na,n_{Na}=\frac{29g}{22.99g/mol}\approx1.26mol\).
The molar mass of \(S\) is \(M_{S} = 32.07g/mol\), moles of \(S,n_{S}=\frac{41g}{32.07g/mol}\approx1.28mol\).
The molar mass of \(O\) is \(M_{O}=16.00g/mol\), moles of \(O,n_{O}=\frac{30g}{16.00g/mol}=1.875mol\).

Step3: Find the mole - ratio

Divide each number of moles by the smallest number of moles (\(n_{Na}\approx1.26mol\)):
For \(Na\): \(\frac{1.26}{1.26} = 1\)
For \(S\): \(\frac{1.28}{1.26}\approx1\)
For \(O\): \(\frac{1.875}{1.26}\approx1.5\)
Multiply each ratio by 2 to get whole - numbers. So the ratio \(Na:S:O = 2:2:3\)

Answer:

100