# Question 7e98d

Jul 13, 2017

$0.49$ $\text{mol S}$

#### Explanation:

Note: I'll assume by the term "gram atom" you mean mole.

We're asked to find the number of moles of $\text{S}$ in $48$ ${\text{g H"_2"SO}}_{4}$.

We can solve this problems in a few steps:

1. Convert the given mass of ${\text{H"_2"SO}}_{4}$ to moles (using its molar mass)

2. Convert the moles of ${\text{H"_2"SO}}_{4}$ to moles of $\text{S}$)

Step 1.

We convert the given mass ($48$ ${\text{g H"_2"SO}}_{4}$) to moles using the molar mass of ${\text{H"_2"SO}}_{4}$.

The molar mass is

(2)overbrace((1.01color(white)(l)"g/mol"))^"hydrogen molar mass" + (1)overbrace((32.07color(white)(l)"g/mol"))^"sulfur molar mass" + (4)overbrace((16.00color(white)(l)"g/mol"))^"oxygen molar mass"

= color(red)(98.08 color(red)("g/mol"

Now converting grams to moles:

48cancel("g H"_2"SO"_4)((1color(white)(l)"mol H"_2"SO"_4)/(98.08cancel("g H"_2"SO"_4))) = color(green)(0.489 color(green)("mol H"_2"SO"_4

Step 2.

Now we recognize that for every molecule of sulfuric acid, there is one atom of sulfur, so we end up with the same number:

color(green)(0.489)cancel(color(green)("mol H"_2"SO"_4))((1color(white)(l)"mol S")/(1cancel("mol H"_2"SO"_4)))

= color(blue)(0.49 color(blue)("mol S"#

rounded to $2$ significant figures.