A.
Physical change
Step by step explanation;:)
MgCl2
Mg=24
Cl=35.5×2 = 71
rmm= 71+24=95g
1 mole = molar mass
1 mole = 95g
1g = 1/95 moles
345g= 1/95 × 345
3.6 moles
Answer:
7 valence electrons.
Explanation:
Oxygen lies in period 2 and group 16 of the periodic table. It is eighth element on the periodic table. Its symbol is O.
Its electronic configuration is given by:
16 = 2,8,6
It has 6 valance electrons. Its valancy is -2. It means can share share and it can gain 2 electron to get stability.
Hence, The element oxygen has <u>7</u> valence electrons.
Spontaneous reaction is a reaction which occurs naturally that is it has capability of proceeding in a given direction without the use of outside source of energy, while non spontaneous reaction is a reaction which require outside source of energy.drag of the appropriate item to their respective bins is a non spontaneous reaction since outside of energy is required to drag the item.
