Nguyên tố R là kim loại kiềm, hiđroxit của R chứa 57,5% khối lượng R. a. Xác định R, Cho biết vị trí của R trong BTH ?

b. Tính thể tích dd H2SO4 0,5M cần trung hoà hết 120 g dd ROH 10% trên ?

9. write the chemical equation for the following word equations. include symbols for physical states in the equation. a. solid zinc sulfide + oxygen gas -> solid zinc oxide + sulfur dioxide gas b. aqueous hydrochloric acid + aqueous barium hydroxide -> aqueous barium chloride + water

Why do scientists look for patterns in the world? a. patterns can explain observations. b. patterns never change, no matter what. c. patterns are easy for scientists to detect. d. patterns are all the same, through all time.

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