Answer:
38
Explanation:
Symbol: Sr
Atomic mass: 87.62 u
Electrons per shell: 2,8,18,8,2
Atomic number: 38
Electron configuration: [Kr] 5s2
Van der Waals radius: 255 pm
Valence electrons: two
Answer: A. Internal energy : May be viewed as the sum of the kinetic and potential energies of the molecules
B. Latent heat: The internal energy associated with the phase of a system.
C. Chemical (bond) energy : The internal energy associated with the atomic bonds in a molecule
D. Nuclear energy : The internal energy associated with the bonds within the nucleus of the atom itself
Explanation:
Internal energy is defined as the total energy of a closed system. Internal energy is the sum of potential energy of the system and the kinetic energy of the system. It is represented by symbol U.
Latent heat is the thermal energy released or absorbed by a thermodynamic system when the temperature of the system does not change. It is thus also called as hidden heat.
Chemical energy is the energy stored in the bonds of molecules.
Nuclear energy is the energy which is stored in the nucleus of an atom called as binding energy within protons and neutrons.
The correct answer is A, B and C
The mass of an atom and the equivalent of to the number of protons and neutrons in the atom
Solute of solution = 17.8 g
Solvn = 198 g
% = 17.8 / 198
w% = 0.089 x 100 = 8.9% by mass
hope this helps!