Burning wood because heat indicates a chemical change
Answer:
B
Explanation:
First of all it is important to know that a half filled orbital is particularly stable. In phosphorus all the electrons occur singly in the 3p sublevel minimizing inter electronic repulsion hence it is more difficult to remove an electron from this energetically stable arrangement. In sulphur, electrons are paired in one of the 3p orbitals thereby lowering the energy of that level due to instability caused by interelectronic repulsion between two electrons in the same orbital.
Answer is: <span>the empirical formula of the hydrocarbon is CH</span>₂.<span>
Chemical reaction: C</span>ₓHₐ + O₂ → xC + a/2H₂O.<span>
m(CO</span>₂) = 33.01 g.
n(CO₂) = m(CO₂) ÷ M(CO₂).
n(CO₂) = 33.01 g ÷ 44.01 g/mol.
n(CO₂) = n(C) = 0.75 mol.
m(H₂O) = 13.52 g.
n(H₂O) = 13.52 g ÷ 18 g/mol.
n(H₂O) = 0.75 mol.
n(H) = 2 · n(H₂O) = 1.5 mol.
n(C) : n(H) = 0.75 mol : 1.5 mol /0.75 mol.
n(C) : n(H) = 1 : 2.
Answer: Endothermic reaction.
Explanation: A chemical reaction in which energy is absorbed from the surrounding environment.
Answer:
true
Explanation: pull in relatively cool water to cool their machinery and let the relatively warm water flow back into the river or lake or sea. ... Water on hot paved surfaces gets hot, then runs off into nearby bodies of water, raising the water temperature
