Consider two reactions. reaction (1) has a constant half-life, whereas reaction (2) has a half-life that gets longer as the reaction proceeds. what can you conclude about the rate laws of these reactions from these observations? a. the first reaction should have a first or a second order, the second one should have an order greater than second. b.the first reaction is a first order reaction, the second one has a second order. c.the first reaction should have a first or a second order, the second one should have an order not less than second. d.the first reaction is a first order reaction, the second one should have an order greater than first.

choice d. The first reaction is a first order reaction, the second one should have an order greater than first.

Explanation:

1) Reaction 1:

It is stated that reaction 2 has a constant half-life time.

Constant half-life time is a characteristic of first order reactions.

This fact is derived from:

r =  k [A] - d[A] / dt = k[A] - d[A] / [A] = k dt- ln [A/Ao] = k tHalf-life ⇒ [A / Ao] = (1/2) - ln (1/2) = k t (half - life) ⇒ t (half-life) = ln (2) / k Since, ln (2) / k is a constant, t (jalf-life) is a constant.

So, the first conclusion is that the first reactions is a first order reaction.

2) Reaction 2.

It is stated that reaction 2 has a half-life that gets longer as the reaction proceeds.

You can suppose r = k [A]ⁿ, where n = 2 (second order reaction)Then, - d[A] / A² = k t1 / [A] = k t + 1 / [Ao]When you solve of t (half-life) you get: t (half-life) = = 1 / ( k [Ao] )This shows that for second order reactions, as the reaction proceeds ([Ao] decreases) the half-life increases.

When you do the same analysis for n > 2 (third or higher order reaction), you get the initial concenration raised to a power greater than two in the denominator, driving to the same conclusion, that as the reaction proceeds the half-life gets longer.

So, your second conclusion is that the seond reaction has an order greater than first.

Summarizing the two general conclusions:

the first reactions is a first order reaction. the second one should have an order greater than first.

That is the choice d. The first reaction is a first order reaction, the second one should have an order greater than first.

What are the options? physical property can be color, smell, opacity, viscosity, density, infra red spectrum, melting and boiling points, attraction and repulson to magnets, etc.

Ibelieve the answer is d. titaniumhope my answer has you : )