Answer is: elements are always combined in the same proportion by mass.
Law of multiple proportions or Dalton's Law said that the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.
For example, nitrogen(I) oxide N₂O; m(N) : m(O) = 2·14 : 16 = 7 : 4.
Another example, water (H₂O) is made of two hydrogen atoms and one oxygen atom:
m(H) : m(O) = 2·1 : 16 = 1: 8.
Answer: B. it will scatter a beam of light
Explanation: hope it is helpful........
Solution..
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Let's calculate the mass of CO₂.
We have (12+(16*2))
= 12+32
=44gmol¯¹..
a. What is the percent by mass of carbon?
Mass of carbon /mass of CO₂ × 100%
12/44 × 100%
=27.3%...
b. What is the percent by mass of oxygen?
Mass of oxygen/mass of CO₂ × 100%
(2×16)/44 × 100%
32/44 × 100%
=72.7%....
To check.. You'll add this two percentage compositions together and see of it gives 100%... If it does then we're good...
27.3%+72.7% = 100%.... Checked..
Hope this helped....?