Water consists of hydrogen and
oxygen, and the approximate ratio, by
mass, of hydrogen to oxygen is 2 : 16.
Approximately how many grams of
oxygen are there in 144 grams of
water ?
(A) 16
(B) 72
(C) 112
(D) 128
(E) 142
OA is D
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hydrogen to oxygen
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adthedaddy
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Here the H:O = 2:16 or 1:8
When you write in fraction, it means in every part there is one part Hydrogen and 8 parts Oxygen. So total parts are 1+8=9
Thus, H= 1/9 and O=8/9
Now, for the given 144gms of water, 144/9= 16gms of each part.
Oxygen has 8 parts out of 9 so 16*8 = 128 is the answer
OR you can multiply directly as 8/9(144)=128
Thus, ans= Option D
When you write in fraction, it means in every part there is one part Hydrogen and 8 parts Oxygen. So total parts are 1+8=9
Thus, H= 1/9 and O=8/9
Now, for the given 144gms of water, 144/9= 16gms of each part.
Oxygen has 8 parts out of 9 so 16*8 = 128 is the answer
OR you can multiply directly as 8/9(144)=128
Thus, ans= Option D
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Jeff@TargetTestPrep
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Solution:grandh01 wrote:Water consists of hydrogen and
oxygen, and the approximate ratio, by
mass, of hydrogen to oxygen is 2 : 16.
Approximately how many grams of
oxygen are there in 144 grams of
water ?
(A) 16
(B) 72
(C) 112
(D) 128
(E) 142
OA is D
We are given that the ratio of hydrogen to oxygen in water, by mass, is 2 : 16. Using our ratio multiplier we can rewrite this as 2x : 16x. We can now use these expressions to determine how much oxygen is in 144 grams of water.
2x + 16x = 144
18x = 144
x = 8
Since x is 8, we know that there are 16 x 8 = 128 grams of oxygen in 144 grams of water.
Answer:D
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