Answer:
The correct answers are:
"Only about 3 percent of Earth's water is fresh water."
"About 75% percent of the fresh water on Earth is frozen in ice sheets."
"The largest source of usable fresh water is groundwater."
Explanation:
3 percent of Earth's water is most certainly fresh water. Confirmed with a few fact checks.
The largest source of usable fresh water on Earth is groundwater. It's more difficult to access but it's there and much more usable than water say frozen in ice on the sea.
The most correct option left would be 75% of Earth's freshwater being in ice sheets even though it's about 70%.
<span>70.4 mg CO2 x 1.0 g /1000 mg x 1 mole CO2/ 44 gCO2 x 1 mole C/1 mole CO2 = 0.0016 moles C
14.4 mg H2O x 1.0 g/1000 mg x 1 mole H2O/18 g H2O x 2 moles H/ 1 mole H2O = 0.0016 moles O
molar mass of C=12 g/mole
molar mass of H=1 g/mole
0.0016 moles C x 12 g C/ 1 mole C = 0.0192 g C or 19.2 mg C
0.00156 moles H x 1 g H/1 mole H = 0.00156 g H or 1.56 mg H
mg O= 30.4 mg vanillin - 19.2 mg C – 1.56 mg H = 9.64 mg O
molar mass of O=16 g/mole
9.64 mg O x 1 g/1000 mg x 1 mole O/16.0 g = 0.000602
C.0016 H.0016 O.000602; divide all the moles by the smallest value of0.000602
C2.66H2.66O1 is the empirical formula;
to obtain whole numbers multiply by 3
3[C2.66H2.66O1] = C8H8O3
above formula weight: 8(C) + 8(H) + 3(O) = 8(12) + 8(1) + 3(16) = 152 amu
The empirical formula weight and the molecular formula weight are the same .
Molecular formula is C8H8O3.</span>
Answer: I would go with D.
Explanation: Sorry if it is incorrect
Answer:
B hotplate beakers thermometers
Explanation: