There are a couple of ways todetermine if a reaction is exothermic or endothermic. Endothermic meaning that heat is added to the reaction to make the reactants interact and exothermic meaning heat is released during the reaction between the two reactants.
In endothermic reactions you can find a triangle above the arrow.
Answer:
Explanation:
Attach is the net ionic equation
Explanation:
Because the place on the map can be changed to another shape by natural effects like faulting,folding , volcanism
Answer: 0.37g
Explanation:avogadro number = 6.02214076x10^23 atoms/molecules per mole
a mole of Na2O = 2*23 + 16 = 52 g
4.25x10^21 atoms = 52*(4.25*10^21/6.02214076*10^23) = 0.37 g
After a chemical change, the substance always changes. It's only after a physical change that the substance does not change. Hope I helped :)
