Answer:
A. 97.8 mm
Explanation:
There are 10 divisions between 9 cm (90 mm) and the end of the ruler (10 cm or 100 mm).
Each division equals 1 mm.
Each 5 mm mark has a longer tick, and the dashed red line is between the 97 mm and 98 mm marks.
You would normally estimate to the nearest tenth of a division. An estimate of 0.8 mm is reasonable.
The length of the object is 97.0 mm + 0.8 mm = 97.8 mm.
B is wrong. You can't possibly estimate to the nearest hundredth of a division.
C is wrong. The dashed red line slightly before the 98 mm mark.
D is wrong. If the dashed red line were exactly on the 98 mm mark, you would record the measurement as 98.0 mm. This indicates that you measured the object to zero tenths on either side of the mark.
Answer: Atoms are single neutral particles, and an ion is a positively or negatively charged particle.
Explanation:
Answer:
The entropy of the final solution decreases, as the reaction disorder is less.
Explanation:
The higher the temperature, the greater the heat of the reaction and the greater the disorder it has, so the entropy will increase ... But this is not the case, since the solution cools, decreasing the entropy proportionally.
Answer:
Percent yield = 90.8%
Explanation:
The reaction of Fe with S to produce FeS is:
Fe + S → FeS
<em>Where the moles of Fe added in excess of S are the moles of FeS</em>
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Now, percent yield is defined as 100 times the ratio between actual yield (13.8g of FeS) and theoretical yield (15.2g FeS):
Percent yield = 13.8g / 15.2g * 100
<h3>Percent yield = 90.8%</h3>