Hoà tan 8g MgO trong 87.6g dd HCl 25%. a. Tính khối lượng muối tạo thành
b. Tính nồng độ phần trăm các dung dịch thu được sau phản ứng

Which element in the third period would you expect to have the larger atomic radius, sodium (na) or sulfur (s)? a. sodium, because it has a higher effective nuclear charge attracting electrons in fewer energy levels. b. sodium, because it has fewer protons attracting electrons in the same energy levels. c. sulfur, because it has more protons attracting electrons in more energy levels. d. sulfur, because it has a higher effective nuclear charge attracting electrons in the same energy levels.

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?

Is 343 in the sequence -5, -2, 1, 4, 7