1) Radioactive decay is the spontaneous decomposition of the unstable nucleus of an atom.
2) The emission of a particle or a photon.
For example, alpha decay is radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus).
3) The result is usually more stable element with smaller atomic number.
For example, in alpha decay atom transforms into an atom with an atomic number that is reduced by two and mass number that is reduced by four.
For example nuclear fission is radioactive decay process in which the nucleus of an atom splits into smaller parts and huge amount of energy is released.
The logarithm from my understanding can never be negative. You can check this on a calculator. You may have a negative if it is shown as -(log x).
Answer:
The energy released as heat when 9.94 g Cu 2 O ( s ) undergo oxidation at constant pressure is -10.142 kJ
Explanation:
Here we have
2Cu₂O ( s ) + O₂ ( g ) ⟶ 4 CuO ( s ) Δ H ∘ rxn = − 292.0 kJ mol
In the above reaction, 2 Moles of Cu₂O (copper (I) oxide) react with one mole of O₂ to produce 4 moles of CuO, with the release of − 292.0 kJ/mol of energy
Therefore,
1 Moles of Cu₂O (copper (I) oxide) react with 0.5 mole of O₂ to produce 2 moles of CuO, with the release of − 146.0 kJ of energy
We have 9.94 g of Cu₂O with molar mass given as 143.09 g/mol
Hence the number of moles in 9.94 g of Cu₂O is given as
9.94/143.09 = 6.95 × 10⁻² moles of Cu₂O
6.95 × 10⁻² moles of Cu₂O will therefore produce 6.95 × 10⁻² × − 146.0 kJ mol or -10.142 kJ.
Chemical. burning is a chemical change
<u>Answer:</u> The correct answer is Option 4: U
<u>Explanation:</u>
Activation energy is defined as the energy that is given to a chemical system with potential reactants to produce products. It is represented as 
It is represented as the energy from the reactants to the activated complex.
Reverse reaction is defined as the reaction in which the products formed become reactants and leads to the formation of reactants back.
So, here, the activation energy of the reverse reaction is the energy between the products and the activated complex, which is represented as letter U in the given graph.
Hence, the correct answer is Option 4: U
