How many significant figures do each of the following measured numbers have, and to what precision have they been measured?
Example: 90 grams has one significant figure and is precise to the nearest ten grams.
1) 1234 liters
2)
3)
4)
3012 grams
890 degrees
901.0 grams
9810. grams
9010 grams
5)
6)
7)
3.465 x 106 meters
8)
3.40 x 103 meters
9)
10)
0.0233 grams
1.000023 grams
0.012 kilometers
7.99 x 10-10 meters
11)
12)
U. S.)

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bcde is the incorrect answer it is a

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol