Bromothymol blue is a chemical indicator that turns blue at ph values greater than 7. in which of these solutions would a blue color be observed if 2 drops of bromothymol blue were added? the concentration of each solution is 0.10 m. ka for hc2h3o2(aq) = 1.8 ´ 10-5, kb for nh3(aq) = 1.8 ´ 10-5

The two solutions are

CH3COOH (acetic acid) : it is a weak acid and will dissociate less (as its Ka is very low) .Even then it will give an acidic solution. The concentration of proton will be less but it will be more than the concentration of hydroxide ions and pH of solution will be less than 7.

Thus bromothymol blue will not turn blue

NH3: ammonia

It is a weak base and will dissociate less to give hydroxide ion. EVen then it will be basic in nature.  The concentration of hydroxide ion will be less but it will be more than the concentration of protons and pH of solution will be more  than 7.

Thus bromothymol blue will  turn blue

answer

fusion: the energy source of stars. the energy released from the collapse of the gas into a protostar causes the center of the protostar to become extremely hot. when the core is hot enough, nuclear fusion commences. fusion is the process where two hydrogen atoms combine to form a helium atom, releasing energy.

hope it

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol