What is the mass grams that are in 3.52 × 10²⁵ molecules of I₂

As you know, one mole of any substance contains exactly

6.022

⋅

10

23

molecules of that substance - this is known as Avogadro's number.

Notice that you're dealing with more than

6.022

⋅

10

23

molecules of carbon dioxide, which means that you'll also be dealing with more than one mole of the compound.

More specifically, you'll have

1.5

⋅

10

26

molecules

⋅

1 mole CO

2

6.022

⋅

10

23

molecules

=

2.491

⋅

10

2

moles CO

2

Now, a substance's molar mass tells what the mass of one mole of that substance is. In carbon dioxide's case, its molar mass is equal to

44.01 g/mol

, which means that every mole of

CO

2

will have a mass of

44.01 g

.

In your case,

2.491

⋅

10

2

moles of

CO

2

would have a mass of

2.491

⋅

10

2

moles CO

2

⋅

44.01 g

1

mole CO

2

=

109.63 g

Rounded to two sig figs, the number of sig figs you have for the number of molecules of

CO

2

, the answer will be

m

C

O

2

=

110 g

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).