Answer: all of them duuuuuuuuuuuuuuuuuuuuuuuuuuuuu
Your answer is D. You're Welcome
<span>1.54 x 10^5 mg
The atomic weight of nickel is 58.6934
Since you have 2.63 moles, the mass will be
2.63 * 58.6934 = 154.3636 grams.
Multiply by 1000 to get milligrams
154.3636 * 1000 = 154363.6 g
Convert to scientific notation
1.543636 x 10^5
Look at the available options and see what matches.
3.56 x 10^5 mg ; Nope, way too big
1.54 x 10^5 mg; Matches to the number of significant figures given.
2.23 x 10^4 mg; Nope, way too small
129 mg; Nope, way too small.</span>
Convert 72g of water into moles of water using molecular weights.
So water is H2O so add up those molecular weights (H=1 and O=16)
2(1)+(16) = 18 g/mol
Then convert so 72g / (18 g/mol) = 4 mol
Now you can convert mol of water to mol of oxygen. So 4 mol of water is 4 mol of oxygen. Then use oxygen molecular weight to find grams again.
4 mol oxygen * 16 g/mol = 64g of oxygen
If we were doing hydrogen instead of oxygen there would be 8 mol hydrogen in 4 mol of water (2 H’s in every H2O molecule) and since we have 74 grams and oxygen is 64 grams, Hydrogen should be 8 grams. Math to check below
8 mol hydrogen * 1 g/mol = 8g of hydrogen
It all adds to 72 so we are correct.
