Nuclear Chemistry - Solving U-238 Activity & Decay Energy

[disneychannel]

Homework Statement

Consider ²³⁸U which undergoes natural radioactive decay to form thorium-234
a)What is the activity, in curies, of 1.00 mg of U-238?
B)What is the energy in kilojoules associated wuth the decay of 1.00 mg of ²³⁸U? The nuvlear mass of throium-235 is 234.0437

Homework Equations

The Attempt at a Solution

A0
0.693/(1.62*10⁵)
=4.27*10^-6 j/k
1*10^-3*(1/238 g)*(6.022*10²³/1 mol)
=2.53*10⁸
my teacher marked this wrong, i don't know why!

B)E=0.0449(9*10¹⁰)
m=(234.0437+4.00150)-238=239.93558

 

[Borek]

You expect us to guess what you did and what are these numbers?

What if I will tell you that 1.521211? Does it make any sense without context?

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methods

 

[gabriels-horn]

=Borek;2727085]You expect us to guess what you did and what are these numbers?

What if I will tell you that 1.521211? Does it make any sense without context?

Agreed; your answers don't even have units.