Answer:
The answer is below
Explanation:
They are isotopes. Isotopes are molecules that have the same atomic number but have different atomic mass because the number of neutrons is different.
Iodine has an atomic mass of 126 g and its atomic number is 53.
# of neutrons = 126 - 53 = 73
Its isotope has an atomic mass of 128 g its atomic number is also 53, but the number of neutrons is different.
# neutrons = 128 -53 = 75
Answer: The Kelvin scale is related to the Celsius scale. The difference between the freezing and boiling points of water is 100 degrees in each, so that the kelvin has the same magnitude as the degree Celsius.
Explanation:
Celsius is, or relates to, the Celsius temperature scale (previously known as the centigrade scale). The degree Celsius (symbol: °C) can refer to a specific temperature on the Celsius scale as well as serve as a unit increment to indicate a temperature interval(a difference between two temperatures or an uncertainty). “Celsius” is named after the Swedish astronomer Anders Celsius (1701-1744), who developed a similar temperature scale two years before his death.
K = °C + 273.15
°C = K − 273.15
Until 1954, 0 °C on the Celsius scale was defined as the melting point of ice and 100 °C was defined as the boiling point of water under a pressure of one standard atmosphere; this close equivalence is taught in schools today. However, the unit “degree Celsius” and the Celsius scale are currently, by international agreement, defined by two different points: absolute zero, and the triple point of specially prepared water. This definition also precisely relates the Celsius scale to the Kelvin scale, which is the SI base unit of temperature (symbol: K). Absolute zero—the temperature at which nothing could be colder and no heat energy remains in a substance—is defined as being precisely 0 K and −273.15 °C. The triple point of water is defined as being precisely 273.16 K and 0.01 °C.
Answer:
Explanation:
a) O₂(g) + 2H₂(g) = 2H₂O
b) H₂O(l) = H₂O(s)
c) NH₃(g) + HCl(g) = NH₄Cl(g)
d) 2NH₄NO₃(s) = 2N₂(g) + O₂(g) + 4H₂O(g)
e) N₂O₄(g) = 2NO₂(g)
ΔS is positive when there is increase in disorderliness. It happens when there is increase in volume .
Increase is volume is maximus in the following reaction.
d) 2NH₄NO₃(s) = 2N₂(g) + O₂(g) + 4H₂O(g)
in this reaction solid NH₄NO₃ is changed to 7 x 22.4 L of gases so there is maximum increase in volume . Hence maximum increase in entropy . Hence ΔS is most positive .
Answer:
16.9 mol
Explanation:
8Al + 3Fe₃O₄ ⟶ 4Al₂O₃ + 9Fe
You want to convert moles of Fe₃O₄ to moles of Al.
The molar ratio is 8 mol Al:3 mol Fe₃O₄. Calculate the moles of Al
Moles of Al = 6.34 × 8/3
Moles of Al = 6.34 × 2.667
Moles of Al = 16.9 mol Al
The total energy required for this conversion is equivalent to the sum of the energies that are used. There are three steps:
1) Heating of liquid acetone
This used 628 J
2) Evaporation of acetone
This used 15.6 kJ or 15,600 J
3) Heating of acetone vapors
This used 712 J
Adding these quantities,
Total energy = 628 + 15,600 + 712
The total energy required was <span>16940 Joules of 16.94 kJ</span>