Answer:
Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:
1) Neutralisation reaction.
2) Combustion reaction.
3) Some oxidation reaction.
Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:
1) Thermal decomposition.
2) Reaction between citric acid and sodium hydrogen carbonate.
It obtains a neutral pH (7). The combination of a strong acid and a strong base results in a neutral pH. The pH of HCl is about 1, and the pH of NaOH is 14.
Answer:
50%
Explanation:
Hydrogen makes up about 50% in glucose in atoms, in mass, 6.7 wise
<span>The molecular mass of sodium oxide (Na2O) is A. 61.97894. The molecular mass of a molecule (Mr) is the sum of atomic masses of its atoms (Ar). The molecular mass of sodium oxide is: Mr(Na2O) = 2 * Ar (Na) + Ar(O). From the periodic table, Ar(Na) = 22.989769 and Ar(O) = 15.9994. The molecular mass of sodium oxide is: Mr(Na2O) = 2 * 22.989769 + 15.9994 = 45.979538 + 15.9994 = 61.97894.</span>