Answers:
1) <span>Breaking Solvent-Solvent Attractions is an Endothermic Process.
2) </span><span>Breaking Solute-Solute Attractions is an Endothermic Process.
3) </span><span>Forming Solute-Solvent Attractions is an Exothermic Process.
Explanation:
When a solute is dissolved in solvent it either releases heat or absorbs heat depending upon the the interactions broken and interactions formed. At first, the solvent solvent interactions are broken , this process requires heat which is provided either from external source or is provided by the forming of solute solvent bond forming process which is exothermic.
When the solvent molecules get apart the solute particles enter to form interactions with elimination of heat. So, if the heat required to break solvent solvent interactions is greater than the heat provided by solute solvent interactions formation then the solute will not dissolve at room temperature and vice versa.</span>
2 valence electrons
Explanation:
Most transition metals have 2 valence electrons. Valence electrons are the sum total of all the electrons in the highest energy level (principal quantum number n). Most transition metals have an electron configuration that is ns2(n−1)d , so those ns2 electrons are the valence electrons.
Explanation:
Zn=65
Cl2= 35+35=70
65+70=135g
1 mole ZnCl2 = 135g
x mole = 17.5g
17.5g × 1 mole/ 135g= 0.129 moles en 17.5g de ZnCl2
4 protons are there in the atom