Dãy các chất được sử dụng với dung dịch HCl loãng tạo thành sản phẩm có chất khí A. BảO, FE, CaCO3 B. Al, MgO, KOH

C. Na2SO3,CaCO3,Zn D. Zn, Fe2O3,Na2So3

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.

give me abc and i will get it for u.

answermeridional ;