Consider this reaction:2HI(g) > H2(g) + I2(g)At a certain temperature it obeys this rate law. rate = (8.74 x 10^-4s^-1) [HI] 1. Suppose a vessel contains HI at a concentration of 0.330M . Calculate the concentration of HI in the vessel 800 seconds later. You may assume no other reaction is important.

0.1440M

Explanation:

Let''s bring out the parameters we were given;

Rate constant = 8.74 x 10^-4s^-1

Initial Concentration [A]o = 0.330M

Final concentration [A]= ?

Time = 800s

The reaction is a first order reaction, due to the unit of the rate constant. In first order reactions, the reaction rate is directly proportional to the reactant concentration and the units of first order rate constants are 1/sec.

Formular relating these parameters is given as;

ln[A] = ln[A]o − kt

Making [A] subject of interest, we have;

ln[A] = ln[A]o − kt

ln[A]  = ln(0.330) - ( 8.74 x 10^-4 * 800)

In[A] = - 1.1086 - (6992 x 10^-4)

ln[A] = -1.8079

[A] = 0.1440M

answer: i would say b.

explanation:

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.