Answer:
<h2><u><em>
internal energy</em></u></h2>
Explanation:
At constant pressure, the heat of reaction is equal to the enthalpy change of the system. Most chemical reactions occur at constant pressure, so enthalpy is more often used to measure heats of reaction than internal energy
Answer:
23892U=23490Th +42He
Explanation:
In alpha decay, the daughter nucleus is two units less than the parent in atomic number. The mass number also decreases by 4 units. The daughter is thus found two places before the parent in the periodic table.
Answer:
Each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements.
Explanation:
