PLEASE HELP ASAP Which two reactions are slower than the others?
A. Silver tarnishes in air that contains hydrogen sulfide.
B. Lead nitrate and potassium iodide react to form a yellow
precipitate.
C. Black powder in fireworks burns explosively to produce white
light
D. Iron metal reacts with oxygen in air to form rust.

A and D takes much slower

Explanation:

Here, we want to select, out of the four given reactions, the one that is slower than the other two

The answers in these case are reactions 1 and 4 ( A and D)

The two reactions show what is called rust (as directly seen in reaction 4)

When we speak of rust, we simply mean a reaction that occurs over time

For example, non coated roofings of houses doesn’t get to change color at an instant

The color degradation that occurs is something that takes some time from the initial time they were used to roof the house

Hence, from these analogy, we can see that these reactions need an an external support to thrive or to come into existence

These external supports are natural forces and they contributing efforts occur over time and cannot be seen immediately

These reactions are thus ones that take much slower time than conventional laboratory reactions in the case of the formation of the precipitate or a reaction that requires a low flash point temperature such as that of black powder to produce such explosive effects

So in conclusion, what we are saying is that the two selected reactions are subjected to the availability of some conditions and may take time to manifest and these absolutely differentiates them from reactions that are spontaneous such as the one having an explosive effect or the other one leading to the formation of a precipitate which takes far less times

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

the ratio of the conjugate base to the acid required to attain the desired ph.