Mass or volume-------------
The number of protons and neutrons in the nucleus : 92 and 146
<h3>Further explanation</h3>
Given
Mass number = 238
Atomic number = 92
Required
Protons and neutrons
Solution
Mass number=number of protons + neutrons
Atomic number=number of protons=number of electrons
Atomic number = 92⇒number of protons=92
Number of neutrons = mass number - atomic number
Number of neutrons = 238 - 92 = 146
Answer:
A. The partial pressure for CH4 = 0.0925atm
B. The partial pressure for C2H6 = 0.925atm
C. The partial pressure for C3H8 = 0.346atm
D. The partial pressure for C4H10 = 0.115atm
Explanation:
Total pressure = 1.48atm
Total mole = 0.4+4+1.5+0.5=6.4
A. Mole fraction of CH4 = 0.4/6.4 = 0.0625
The partial pressure for CH4 = 0.0625 x 1.48 = 0.0925atm
B. Mole fraction of C2H6 = 4/6.4 = 0.625
The partial pressure for C2H6 = 0.625 x 1.48 = 0.925atm
C. Mole fraction of C3H8 = 1.5/6.4 = 0.234
The partial pressure for C3H8 = 0.234 x 1.48 = 0.346atm
D. Mole fraction of C4H10 = 0.5/6.4 = 0.078
The partial pressure for C4H10 = 0.078 x 1.48 = 0.115atm
Answer:
70.15 cm³
Solution:
Data Given;
Mass = 55 g
Density = 0.784 g.cm⁻³
Required:
Volume = ?
Formula Used:
Density = Mass ÷ Volume
Solving for Volume,
Volume = Mass ÷ Density
Putting values,
Volume = 55 g ÷ 0.784 g.cm⁻³
Volume = 70.15 cm³
Answer: (E) 300 bq
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.
Half life is represented by 
Half life of Thallium-208 = 3.053 min
Thus after 9 minutes , three half lives will be passed, after ist half life, the activity would be reduced to half of original i.e. 
, after second half life, the activity would be reduced to half of 1200 i.e. 
, and after third half life, the activity would be reduced to half of 600 i.e. 
,
Thus the activity 9 minutes later is 300 bq.
