Answer:
After 18 hours, the amount of pure technetium that will be remaining is 12.5 grams
Explanation:
To solve the question, we note that the equation for half life is as follows;

Where:
N(t) = Quantity of the remaining substance = Required quantity
N₀ = Initial radioactive substance quantity = 100 g
t = Time duration = 18 hours
= Half life of the radioactive substance = 6 hours
Therefore, plugging in the values, we have;

Therefore, after 18 hours, the amount of pure technetium that will be remaining = 12.5 grams.
A chemical reaction between solar ultraviolet radiation and an atmosphere polluted with hydrocarbons and oxides of nitrogen causes photochemical smog. ... Smog can happen both during the day and at night, but photochemical smog only happens in the presence of sunlight.
Answer:
1.89 nol Cu(NO3)2
Explanation:
if you calculate it it will be 1.89
Answer: Option C. p-dichlorobenzene and 1,4-dichlorobenzene.
Explanation:
A line-angle formula with six vertices and a circle inscribed corresponds to the compound known as benzene.
Further, according to the IUPAC standards for naming benzene derivatives, you must first number the position of the substituent. In this case, the substituents (chloros) are located at the positions 1 and 4; also, for the benzene derivatives when they have 2 substituents and the positions are 1 and 4, this configuration is known as <em>para </em>or <em>p </em>configuration.
Additionally, this compound has 2 substituents (chloros) so you have to indicate this number (di).
Therefore, the correct answer is C. p-dichlorobenzene and 1,4-dichlorobenzene.