Answer:
natural income
Explanation:
Living sustainably in the 21st century means coexisting with the nature. In other words, to live sustainably means to meet the needs of the human without affecting or degrading the mother nature.
In the context, living sustainably means to live from the natural income from the nature's gift to us, using their natural resources and not hurting them or exploiting them. They may be resources from the soil, plants, clean air, animals, nature's clean water,etc.
It is possible because the electrons in the energy level furthest from the nucleus delocalise, this leaves behind positively charged metal ions which are attracted to the negatively charged electrons that now move around the lattice freely
2Al(No3)3(aq) + 3Ba(OH)2(aq) ------------> 2Al(OH)3(s) + 3Ba(NO3)2(aq)
Ca(s) + ZnBr2(aq) -------------------> Zn(s) + CaBr2(s)
CuSO4(aq) + Na2S(aq) --------------> CuS(s) + Na2SO4(aq)
KBr(aq) + Pb(Cl3)2(aq) -----------------> PbBr2(s) + K(ClO3)(aq)