9514 1404 393
Answer:
water
Step-by-step explanation:
Comparison of numbers can be done a couple of different ways. One way is to subtract one from the other. If the difference is positive, the minuend (first number) is the larger of the two.
Another way is to divide one number by the other. If the ratio is more than 1, then the numerator is the larger number.
For numbers in scientific notation, the division is perhaps the easiest. Here, that gives you ...
[tex]\displaystyle\frac{\text{water mass}}{\text{oxygen mass}}=\frac{2.99\times10^{-26}\text{ kg}}{2.66\times10^{-26}\text{ kg}}=\frac{2.99}{2.66}\approx 1.12[/tex]
This value is greater than 1, so the mass of a water molecule is greater.
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You will note that the multipliers (10^-26 kg) cancelled because they were equal. If they are unequal, the usual rules of exponents apply.
