Answer:
<em>2.085 x 10^-20 J</em>
<em></em>
Explanation:
minimum energy required to produce photoelectric effect in chromium is given as hf = 7.21 x 10^-19 J
The work function of chromium Ф = 4.37 eV = 7.00151 x 10^-19 J
The minimum energy required to eject an electron from from a chromium metal E = ?
From E = hf - Ф
substituting values, we have
E = (7.21 x 10^-19) - (7.00151 x 10^-19)
E = <em>2.085 x 10^-20 J</em>
A chemical property of soda ash is that it is an alkaline compound , of pH 11.6 in aqueous solution. The chemical name of soda ash is sodium carbonate. It is a sodium salt of carbonic acid and occurs as a white crystalline compound. It has a cooling alkaline taste. It can be found in the ashes of many plants. It is produced in large quantities from sodium chloride (common salt). It can be found as a mineral in mineral deposits of natron usually in seasonal lakes when the lakes dry up.
(2) U-238 is the radioisotope used in dating geological formations. Uranium-238 has a half-life of 4.46 billion years, which makes it suitable to date such old formations.
The other options do not have such long durabilities and half-lives.
A.92 all Uranium atoms contain the same amount of protons
Since acetic acid or vinegar boils sooner than water and vinegar and water are highly miscible, we cant separate the two by filtration but one way is to use their volatilities. We can boil the solution at 100oC and thats the time, water remains in the container.
