Answer:
2H2(g) + O2(g) --------> 2H2O(g). ∆H= -242KJmol-1
Explanation:
A thermochemical equation is a balanced chemical reaction equation that includes the physical states of all reactants and products and the energy change.
As shown above, hydrogen reacted with oxygen in the gas phase to form water, an energy of 242KJ was evolved and we are required to put this in a thermochemical equation using the least coefficients.
Hydrogen reacts with oxygen to form water in the gas phase in a least ratio of 2:1 as shown in the answer.
The term 'energy evolved' in the question means that the reaction is exothermic and energy is evolved. Hence ∆H is negative as shown.
Answer:
2H2 + O2 -----> 2H2O
Not sure about the second question though.
Electronegativity refers to the ability of an atom to attract shared electrons in a covalent bond. The higher the value of the electronegativity, the more strongly that element attracts the shared electrons.
Answer:
The mouth uses both mechanical and chemical digestion. Mechanical digestion involves physically breaking down the food into smaller pieces (using the jaw/teeth). However, chemical digestion then takes over and starts breaking down the food into simpler nutrients that can be used by the cells using saliva, which is naturally made within the mouth.
Hope this helps you! Have a great day! :D
Answer:
+2.5
Explanation:
So the oxidation number of S in Na2S4O6is +2.5.