Explanation is in the file
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Answer:
C phosphorus has 5 bond sites.
Answer:
The new pressure of the gas is 57.69atm
Explanation:
P1 = 50 atm
T1 = 390K
T2 = 450K
P2 = ?
This problem requires pressure law.
Pressure law states that the pressure of a fixed mass of gas is directly proportional to its temperature provided volume remains constant.
Mathematically,
P = kT, k = P / T
P1 / T1 = P2 / T2 = P3 / T3 .......Pn /Tn
P1 / T1 = P2 / T2
Solve for P2,
P2 = (P1 * T2) / T1
P2 = (50 * 450) / 390
P2 = 57.69atm
The new pressure of the gas is 57.69atm
Answer:
A. To be precise, it must be able to make measurements repeatedly over a long period of time.
Explanation:
The precision of a scientific measuring tool can be defined as how close the values between multiple measurements are to each other, when repeated under the same conditions.
This ultimately implies that, the precision of a scientific measuring tool reflects the reproducibility and repeatability of its measurements, irrespective of how accurate the measurements are.
In science, one of the most effective ways to determine the precision of a scientific measuring tool is to find the difference between the highest and lowest measurements (measured values).
Hence, the statement which correctly describes a characteristic that a scientific measuring tool should have is that, to be precise, it must be able to make measurements repeatedly over a long period of time.
4Fe(s) + 3O2(g) → 2Fe2O3(s) ....... ΔH = -1.7 x 10^3 kJ
<span>shows that 1700 kJ of heat is released when 4 moles of Fe react. </span>
<span>Molar mass of Fe = 56 g/mol </span>
<span>Molar mass of Fe2O3 = 160 g/mol. </span>
<span>(a) When 4 mol ( 4 x 56 = 224 g) iron reacted 1700 kJ are released, </span>
<span>when 9.0 g Fe reacted, the amount of energy will be </span>
<span>(9.0 x 1700) / (224) = 68.3 kJ </span>
<span>(b) According to the equation, 1700 kJ of energy released during the formation of 2 moles of Fe2O3 which is 2 x 160 = 320 g of rust. </span>
<span>120 kcal x (4.18 kJ / 1 kcal) = 501.6 kJ </span>
<span>When 1700 kJ released = 320 g rust </span>
<span>when 501.6 kJ released = (501.6 x 320) / 1700 = 94.4 g rust</span>