Nêu ý nghĩa cách viết 2S 5CO2 4NaHCO3 7Cl 8H2 4H2SO4 5Fe

2 câu trả lời

Đáp án: 2 nguyên tố lưu huỳnh 2S

5 nguyên tố cacbonic 5 CO2

4 nguyên tố Natri bicacbonat 4NaHCO3

7 nguyên tố clorua 7Cl

8 nguyên tố hiđro 8H2

4 nguyên tố axit sunfuric 4H2SO4

5nguyên tố sắt 5Fe

Giải thích các bước giải:

Đáp án:

Giải thích các bước giải: 2 nguyên tử của nguyên tố lưu huỳnh

7 nguyên tử của nguyên tố Clo

5 nguyên tử của nguyên tố sắt

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