How Do You Calculate the Mass of Atom Type B?

  • Thread starter Thread starter JakePearson
  • Start date Start date
AI Thread Summary
To calculate the mass of atom type B, first determine the total mass of type A atoms by multiplying the number of type A atoms (4x10^5) by their mass (5x10^-26 kg), resulting in a total mass of 2x10^-20 kg. Next, subtract this total mass of type A from the overall mass of the gas (2.8x10^-20 kg) to find the total mass of type B atoms, which is 8x10^-21 kg. Finally, divide the total mass of type B by the number of type B atoms (8x10^5) to find the mass per atom of type B. This process involves multiplication and division rather than subtraction to arrive at the correct mass of type B atoms. Understanding these calculations is essential for accurate atomic mass determination.
JakePearson
Messages
52
Reaction score
0
a gas contains 2 kinds of atoms 4x105atoms of type A and 8x105 atoms of type B. it is known that the mass of type A atoms is 5x10-26kg and the mass of the gas is 2.8x10-20kg. what is the mass of type B atom?

answer;
2.8x10-20kg - 5x10-26kg = 2.8x10-20kg - 0.00005x10-20 = 2.799995x10-20kg

is this correct
 
Physics news on Phys.org
Not really. Think about it. You know the mass of EACH type A atom. You also know how many of them there are. Therefore, you can figure out the total mass due to type A by carrying out a certain arithmetic operation (and, no, it is not subtraction).

Once you have the total mass of type A, THEN you can subtract it from the total mass of gas, which will give you the total mass due to type B.

If you know the total mass of the type B gas, and you know how many atoms there are, then the mass PER atom can be calculated using yet another arithmetic operation (that is not subtraction either)
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...

Similar threads

Replies
7
Views
1K
Replies
17
Views
5K
Replies
38
Views
4K
Replies
6
Views
1K
Replies
16
Views
1K
Replies
3
Views
2K
Replies
17
Views
2K
Back
Top