Answer:
B) As you move across the row, the number of electrons increases and reactivity also increases.
Explanation:
The periodic table is arranged in a way that if you go across a period, the number of protons, neutrons, and electrons in an element increases. In terms of reactivity, the most reactive elements are the ones which have a high electronegativity. The electronegativity of the elements increases as you travel to the right and upwards on the periodic table.
Answer: -105 kJ
Explanation:-
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=\sum [n\times B.E(reactant)]-\sum [n\times B.E(product)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Csum%20%5Bn%5Ctimes%20B.E%28reactant%29%5D-%5Csum%20%5Bn%5Ctimes%20B.E%28product%29%5D)
![\Delta H=[(n_{N_2}\times B.E_{N_2})+(n_{H_2}\times B.E_{H_2}) ]-[(n_{NH_3}\times B.E_{NH_3})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BN_2%7D%5Ctimes%20B.E_%7BN_2%7D%29%2B%28n_%7BH_2%7D%5Ctimes%20B.E_%7BH_2%7D%29%20%5D-%5B%28n_%7BNH_3%7D%5Ctimes%20B.E_%7BNH_3%7D%29%5D)
![\Delta H=[(n_{N_2}\times B.E_{N\equiv N})+(n_{H_2}\times B.E_{H-H}) ]-[(n_{NH_3}\times 3\times B.E_{N-H})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BN_2%7D%5Ctimes%20B.E_%7BN%5Cequiv%20N%7D%29%2B%28n_%7BH_2%7D%5Ctimes%20B.E_%7BH-H%7D%29%20%5D-%5B%28n_%7BNH_3%7D%5Ctimes%203%5Ctimes%20B.E_%7BN-H%7D%29%5D)
where,
n = number of moles
Now put all the given values in this expression, we get
![\Delta H=[(1\times 945)+(3\times 432)]-[(2\times 3\times 391)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%281%5Ctimes%20945%29%2B%283%5Ctimes%20432%29%5D-%5B%282%5Ctimes%203%5Ctimes%20391%29%5D)
Therefore, the enthalpy change for this reaction is, -105 kJ
Answer: C) To monitor weather event restricted several days in advance.
Explanation:
Answer: 2NOBr(g) ⇌ 2NO(g) + Br2(g)
Explanation: For volume changes in equillibrium, the following are to be taken into consideration:
- Volume changes have no effect on equillibrium system that contains solid or aqueous solutions.
- An increase in volume of an equilibrium system will shift to favor the direction that produces more moles of gas.
- A decrease in volume of an equilibrium system will shift to favor the direction that produces less moles of gas.
- Volume changes will have no effect on the equillibrium system if there is an equal number of moles on both sides of the reaction.
2NOBr(g) ⇌ 2NO(g) + Br2(g) is the equillibrium system because there are more moles of products,therefore an increase in the volume of the reaction will shift to the right and produce more moles of products. Also both reactants and products exist in the gaseous state and does not have equal number of moles.
