Answer:
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- <u><em>C) How much energy was added to the substance to increase molecule motion? </em></u>
Explanation:
<em>The most relevant question to ask regarding this change</em> must take into account the physical knowledge about matter.
When matter changes from<em> liquid </em>state to <em>gaseous</em> state, a physical change called evaporation, the particles (molecules or atoms) of the <em>pure substance </em>will separate from each other, take up more space and move faster.
<em>Condensation</em> is the opposite to evaporation, thus the option A) is not the most relevant question.
<em>The charge of the particles</em> does not change; so the option B) is not relevant at all.
The particles should gain energy from the surroundings to <em>increase</em> their <em>motion</em> (kinetic energy) when they pass from liquid state, where they move slower, to gas state, where they move faster. Hence, the option<em> C), How much energy was added to the substance to increase molecule motion?</em> , is totally relevant.
Since this is an increase in the <em>kinetic energy of the molecules</em>, the option D) is not relevant.
Answer :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and the unpaired electrons present in the molecule.
The given molecule is, 
Beryllium has '2' valence electrons and fluorine has '7' valence electrons. Beryllium is the central atom and fluorine is the terminal atom.
Total number valence electrons in = 2 + 2(7) = 16
According to the Lewis-dot structure, there are '4' number of bonding electrons and 12 number of non-bonding electrons (lone-pair).
The Lewis-dot structure is shown below.
Answer:
188.03K
Explanation:
The following data were obtained from the question:
T1 (initial temperature) =273K
V1 (initial volume) = 400mL
P1 (initial pressure) = 760mmHg
P2 (final pressure) = 380mmHg
V2 (final volume) = 551mL
T2 (final temperature) =?
Applying the general gas equation P1V1/T1 = P2V2/T2, the final temperature of the gas can be obtained as follow:
P1V1/T1 = P2V2/T2
760 x 400/273 = 380 x 551/T2
Cross multiply to express in linear form as shown below:
760 x 400 x T2 = 273 x 380 x 551
Divide both side by 760 x 400
T2 = (273 x 380 x 551)/(760 x 400)
T2 = 188.03K.
Therefore, at a temperature of 188.03K, the gas sample will have a volume of 551mL
In order to calculate the experimental percent error, we follow these steps:
1- Subtract one value from the other (order does not matter as we take absolute)
2- Divide the obtained number by the accepted or true value.
3- Multiply the fraction you got from step 2 by 100 to get the percentage of error.
Now, we will apply these steps on our problem:
1- Subtract one value from the other:
9.95 - 7.13 = 2.82
2- Divide by accepted value:
2.82 / 7.13 = 0.3955
3- Multiply by 100 to get the error percentage:
error percentage = 0.3955 x 100 = 39.55%
