Answer:
[tex]\boxed {\boxed {\sf A. \ 54 \ grams }}[/tex]
Explanation:
To convert from moles to grams, we must use the molar mass.
Recall that water's molecular formula is H₂O. It contains hydrogen and oxygen. Look up the two elements masses on the Periodic Table.
Now, use these masses to find water's mass. The subscript of 2 tells us there are 2 atoms of hydrogen, so we multiply hydrogen's mass by 2 and add oxygen's.
Use the molar mass as a ratio.
[tex]\frac{18.015 \ g \ H_2 O}{ 1 \ mol \ H_2 O}[/tex]
Multiply by the given number of moles.
[tex]3 \ mol \ H_2O*\frac{18.015 \ g \ H_2 O}{ 1 \ mol \ H_2 O}[/tex]
The moles of water will cancel.
[tex]3 *\frac{18.015 \ g \ H_2 O}{ 1 }[/tex]
[tex]3 *{18.015 \ g \ H_2 O}[/tex]
[tex]54.045 \ g \ H_2O[/tex]
Round to the nearest whole number. The 0 in the tenth place tells us to leave the number as is.
[tex]54 \ g \ H_2O[/tex]
There are about 54 grams of water in 3 moles.
Answer:
54 grams
Explanation:
First step is to find what one mole of water is in grams.
Water is H2O so that means we have two moles of Hydrogen.
H - 2 grams (on periodic table)
We have one mole of Oxygen.
O - 16 grams (on periodic table)
Add 2 and 16 to get 18 total grams in one molecule of H2O
Now multiply 3 times 18 to know how many grams in 3 moles of H2O
You end with
3x18=54 grams
