How is an exothermic reaction indicated in an equation? A. Heat is written above the arrow in the equation. B. Heat is included as one of the reactants. C. Heat is included as one of the products. D. Heat is added to both sides of the equation.​

If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin?

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.

Who discovered a pattern to the elements in 1869?