Không tính toán cụ thể mà lý luận để : a) Xác định chất giàu oxi nhất: Al2O3, N2O3, P2O3, Fe, O3, Cl2O3.
b) Sắp xếp các chất sau theo thứ tự hàm lượng sắt giảm dần: FeS, FeS2, FeO, Fe3O4, Fe2O3, FeSO3, FeSO4, Fe2(SO4)3.
c) Tìm những chất có hàm lượng đồng bằng nhau trong 4 chất : CuO, Cu2O, CuS, Cu2S.

Start an single atom tab. observe the decay of polonium-211. after each decay, press the reset nucleus button to watch the process again. write a description of alpha decay for po-211

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.

Enzymes affect the reactions in living cells by changing the