Answer:
Explanation:
13 ) symbol of enthalpy change = Δ H .
14 ) enthalpy change is nothing but heat absorbed or evolved .
During fusion enthalpy change
Δ H .= m Lf , m is mass and Ls is latent heat of fusion
During evaporation, enthalpy change
Δ H .= m Lv , m is mass and Lv is latent heat of evaporation
during temperature rise , enthalpy change
Δ H = m c Δ T
In case of gas , enthalpy change can be calculated by the following relation
Δ H = Δ E + W , Δ E is change in internal energy , W is work done by gas.
15 ) When enthalpy change is negative , that means heat is released to the environment .So reaction is called exothermic .
when heat is absorbed enthalpy change is positive . Reaction is endothermic.
Answer:
H- hydrogen
Explanation: Hydrogen is in the first group meaning that it only has 1 valence electron and 1 energy level
Answer: C.) SO2
Explanation: Sulfur Dioxide is the gaseous molecule which can show the resonance through lewis dot structure due to the presence of lone pairs of electrons present on all of the three atoms of the molecules. Moreover , Sulphur forms pie bond with the oxygen using p orbitals which forms a network of the conjugated system that help to elaborate the reason of the formation of the resonance structure.
Options (a), (b), and (d) cannot form resonating structures as they involve the formation of the chemical bonds through single sigma bond.
First, the symbol for sodium oxide is Na₂O
Each Na (sodium) has a charge of 1+, and each O has a charge of 2- :
Na₂¹⁺O²⁻
There are two Na's, however, and each one is 1+, however, so the Na₂ has a total charge of 2+. Because of this, the 2+ from the 2 Na's and the 2- from the O cancel each other out to make 0.
