Which is a sign that a chemical reaction may have taken place?
- ASugar dissolves completely when stirred into water
- BA block of wax melts when it is heated
- CWater freezes into ice when put in a freezer
- DA gas is produced when two liquids are mixed
Which is a sign that a chemical reaction may have taken place?
What are the usual units of molar mass?
Which process is exothermic (releases heat)?
On an energy diagram, the products are at a lower energy than the reactants. What kind of reaction is shown?
สารใดถูกออกซิไดซ์ในปฏิกิริยา 2Mg + O₂ → 2MgO
ตามทฤษฎีจลน์ของโมเลกุล อุณหภูมิวัดอะไร
An unknown element is shiny, conducts electricity, and reacts vigorously with water to form a basic solution and hydrogen gas. In which group is it most likely?
ธาตุหนึ่งมีการจัดเรียงอิเล็กตรอน 2, 8, 7 ธาตุนี้มีแนวโน้มเกิดไอออนชนิดใดมากที่สุด
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