<span>Balanced nuclear reaction: 234/91 Pa → 4/2 He + 230/89 Ac.
1) number of protons and neutrons on both side of nuclear reaction must be the same. There are 91 protons (atomic number) and 143 neutrons (mass number - atomic number, 234 - 91 = 143 or (4-2) + (230 - 89) = 143)) on both side of reaction.
2) a</span>lpha
decay is radioactive decay<span> in which
an atomic nucleus emits
an alpha particle (helium
nucleus) and transforms into an atom with an atomic
number that is reduced by two and mass number that is reduced by four, so atomic mass of new element is 89 (91 - 2) and mass number is 230 (234 - 4 = 230).
3) look at atomic number, element with atomic number 89 is actinium.</span>
Answer:
The new volume after the temperature reduced to -100 °C is 0.894 L
Explanation:
Step 1: Data given
Volume of nitrogen gas = 1.55 L
Temperature = 27.0 °C = 300 K
The temperature reduces to -100 °C = 173 K
The pressure stays constant
Step 2: Calculate the new volume
V1/T1 = V2/T2
⇒with V1 = the initial volume of the gas = 1.55 L
⇒with T1 = the initial temperature = 300 K
⇒with V2 = the new volume = TO BE DETERMINED
⇒with T2 = the reduced temperature = 173 K
1.55 L / 300 K = V2 / 173 K
V2 = (1.55L /300K) * 173 K
V2 = 0.894 L
The new volume after the temperature reduced to -100 °C is 0.894 L
Answer: There are 7.4 moles of helium gas present in a 1.85 liter container at the same temperature and pressure.
Explanation:
Given: 
= 2.25 L, 
= 9.0 mol
= 1.85 L, 
= ?
Formula used to calculate the moles of helium are as follows.
Substitute the values into above formula as follows.
Thus, we can conclude that there are 7.4 moles of helium gas present in a 1.85 liter container at the same temperature and pressure.
Answer:
higher, higher
Explanation:
It takes more energy to rip apart stronger bonds (that's mostly just common sense there). The boiling point increases because it would take more energy to get the molecules to go from a stuck together liquid, to separating in a gaseous form.
