Answer:
D
Explanation:
∆H° = ∆Hf ° (products) – ∆Hf ° (reactants)
This is because U-235 decays naturally by a process known as alpha radiation. This means that it releases an alpha particle (two neutrons and two protons connected together).
Another reason that U-235 is ideal for producing nuclear power is that unlike most materials, U-235 can undergo induced fission. When a free neutron collides with a U-235 nucleus, the nucleus will usually capture the neutron and split extremely quickly. The splitting of a single U-235 atom can release roughly 200 MeV (million electron volts).
the molar mass of the element is 81.36 g/mol
<u><em>calculation</em></u>
step 1 : multiply each %abundance of the isotope by its mass number
that is 79.95 x 29.9 =2391
81.95 x 70.1 = 5745
Step 2: add them together
2390.5 + 5744.7 =8136
Step 3: divide by 100
= 8136/100 = 81.36 g/mol
Answer:
6. In order from left to right the balanced coeficcients are,
6, 1, 2, 3
8. 
9. In order from left to right the balanced coeficcients are,
1, 11, 7, 8