Answer:
Cl
Explanation:
The element Cl will have the strongest ionization energy from the given choices. Most non-metals have higher ionization energy compared to metals.
Ionization energy is the energy required to remove the most loosely held electron from the gaseous phase of an atom.
- As you go from left to right on the periodic table, it increases progressive
- From top to bottom, the ionization energy reduces significantly.
- The attractive force between the protons in the nucleus and the electrons plays a very important role.
- In metals, they have very large atomic radius, the attractive force on the outer electrons is very weak.
- This is not the case in non-metals
The accuracy is associated with magnitude of fractional error or relative error in that measurement
the precision of a measurement is associated with least count of the measuring instrument.
precision does not mean accuracy but both are highly demanded while making measurements in physics.
Answer:
1st answer: A. nitrogen
2nd answer: A. Sodium carbonate
Explanation:
First, consider the steps to heat the sample from 209 K to 367K.
1) Heating in liquid state from 209 K to 239.82 K
2) Vaporaizing at 239.82 K
3) Heating in gaseous state from 239.82 K to 367 K.
Second, calculate the amount of heat required for each step.
1) Liquid heating
Ammonia = NH3 => molar mass = 14.0 g/mol + 3*1g/mol = 17g/mol
=> number of moles = 12.62 g / 17 g/mol = 0.742 mol
Heat1 = #moles * heat capacity * ΔT
Heat1 = 0.742 mol * 80.8 J/mol*K * (239.82K - 209K) = 1,847.77 J
2) Vaporization
Heat2 = # moles * H vap
Heat2 = 0.742 mol * 23.33 kJ/mol = 17.31 kJ = 17310 J
3) Vapor heating
Heat3 = #moles * heat capacity * ΔT
Heat3 = 0.742 mol * 35.06 J / (mol*K) * (367K - 239.82K) = 3,308.53 J
Third, add up the heats for every steps:
Total heat = 1,847.77 J + 17,310 J + 3,308.53 J = 22,466.3 J
Fourth, divide the total heat by the heat rate:
Time = 22,466.3 J / (6000.0 J/min) = 3.7 min
Answer: 3.7 min
