Hi!
First of all, the melting of ice cream is not a chemical reaction, because there is no change in the components of the ice cream and if you freeze the ice cream again, you will get the same ice cream that you had previously.
The melting of ice cream is an example of a physical change, in which a substance goes from solid to liquid state, and it is an endothermic physical change.
When you freeze ice cream, the heat is removed from the ice cream, making it an exothermic process, when heat is liberated to the environment and it's taken away from the substance, in this case, the ice cream.
The answer to this question would be: 2.36 mol
To answer this question, you need to know the molecular weight of copper. Molecular weight determines how much the weight of 1 mol of a molecule has. Copper molecular weight about 63.5g/mol. Then, the amount of mol in 150g copper should be: 150g / (63.5g/mol)= 2.36 mol
Answer:
Phosphorus has a low melting point because the intramolecular forces holding it together is London Dispersion Forces.
Explanation:
London Dispersion Forces (LDF) are the weakest intramolecular forces. You don't need to break the covalent bonds, but rather the Van Der Waals' Forces. If LDF are the weakest forces, then the melting point is low.
Answer;
-(2) An atom is mostly empty space.
Experiment
-Rutherford conducted the "gold foil" experiment where he shot alpha particles at a thin sheet of gold. The conclusion that can be drawn from these experiment is that an atom is mostly empty space.
-Rutherford found that a small percentage of the particles were deflected, while a majority passed through the sheet. This caused Rutherford to conclude that the mass of an atom was concentrated at its center, as the tiny, dense nucleus was causing the deflections.
1 valence electron in alkali metals.