Answer:
Matter is the "stuff" that makes up the universe everything that takes up space and has mass is matter.
All matter is made up of atoms, which are in turn made up of protons, neutrons and electrons
They are about 4.5 billion years old. Hope this helps.
Answer:
This reaction is exothermic because the system shifted to the left on heating.
Explanation:
2NO₂ (g) ⇌ N₂O₄(g)
Reactant => NO₂ (dark brown in color)
Product => N₂O₄ (colorless)
From the question given above, we were told that when the reaction at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color.
This simply means that the reaction does not like heat. Hence the reaction is exothermic reaction.
Also, we can see that when the temperature was increased, the reaction turned dark brown in color indicating that the increase in the temperature favors the backward reaction (i.e the equilibrium shift to the left) as NO₂ which is the reactant is dark brown in color. This again indicates that the reaction is exothermic because an increase in the temperature of an exothermic reaction will shift the equilibrium position to the left.
Therefore, we can conclude that:
The reaction is exothermic because the system shifted to the left on heating.
13.6
a) yes Pb is more reactive that Ag, Pb before Ag
b) no, Cu after H
c) yes, Cl2 is more active than I2
4) yes, Mg is more active
13.7 (as I think)
Al ³⁺ more active than Zn²⁺, Mn can react with Zn²⁺, but not with Al ³⁺ , because Mn after Al but before Zn