Answer:
The atomic number on the Periodic Table identifies the number of protons in any atom of that element. Copper, atomic number 29, has 29 protons. Finding the atomic number of an element reveals the number of protons.
To find the number of neutrons in the atom, subtract the atomic number from the atomic mass.
Answer:
The expression to calculate the mass of the reactant is 
Explanation:
<em>The amount of heat released is equal to the amount of heat released per gram of reactant times the mass of the reactant.</em> To keep to coherence between units we need to transform 1,080 J to kJ. We do so with proportions:

Then,

The answer is D, because "Animals without a backbone are invertebrates."
Answer:
Reaction A and B are unfavorable.
Explanation:
Gibbs free energy is an energy which that can be use to convert into useful work.
ΔG°=ΔH°-TΔS°
ΔG°= Gibbs free energy
ΔH° = enthalpy of reaction
T = temperature of eh reaction
ΔS° = Entropy change
- If the Gibbs free energy of the reaction is positive than the reaction will be non spontaneous and the chemical reaction will be not feasible.
- If the Gibbs free energy of the reaction is negative than the reaction will be spontaneous and the chemical reaction will be feasible .
According to given information in the question:
Reaction A and B are non spontaneous as their Gibbs free energy value is positive.hence both are unfavorable.