The given question is incomplete. The complete question is as follows.
Which of the following best helps explain why an increase in temperature increases the rate of a chemical reaction?
(a) at higher temperatures, high-energy collisions happen less frequently.
(b) at low temperatures, low-energy collisions happen more frequently.
(c) at higher temperatures, less-energy collisions happen less frequently.
(d) at higher temperatures, high-energy collisions happen more frequently
Explanation:
When we increase the temperature of a chemical reaction then molecules of the reactant species tend to gain kinetic energy. As a result, they come into motion which leads to more number of collisions within the molecules.
Therefore, chemical reaction will take less amount of time in order to reach its end point. This means that there will occur an increase in rate of reaction.
Thus, we can conclude that the statement at higher temperatures, high-energy collisions happen more frequently, best explains why an increase in temperature increases the rate of a chemical reaction.
Answer:
H2O> NH3> CH4
Explanation:
According to valence shell electron pair repulsion theory (VSEPR), bond angles and repulsion of electron pairs depends on the nature of electron pairs on the central atom of the molecule. Lone pairs cause more repulsion (and distortion of bond angles) than bond pairs). Lone pair- lone pair repulsion is greater than lone pair bond pair repulsion.
Water contains two lone pairs on oxygen hence it experiences the greatest repulsion. Ammonia has only one lone pair on nitrogen hence there is lesser repulsion between lone pairs and bond pairs. Methane possess only bond pairs of electrons hence it has the least repulsion.
The compound which is ionic is Kh
Kh is ionic because ionic compound is made between a metal and a non metal. K( potassium) is a metal while H (hydrogen) is a non metal. The bond between potassium and hydrogen form ionic bond whereby potassium loses one electron and hydrogen gain one electron to form an ionic compound.
Environmental contingency plan is important to lessen or even prevent casualties or damage to infrastructures when unexpected environmental disasters happen. This is a common management strategy to lessen the costs of the company in the future. More importantly, it is used for safety purposes.