Fluoride ion is poisonous in relatively low amounts: 0.2 g of f− per 70 kg of body weight can cause death. nevertheless, in order to prevent tooth decay, f− ions are added to drinking water at a concentration of 1 mg of f− ion per l of water.

how many liters of fluoridated drinking water would a 70−kg person have to consume in one day to reach this toxic level?
answer in scientific notation

liters of fluoridated drinking water would a 70−kg person have to consume in one day to reach this toxic level

Explanation:

1g =1000mg

So,

is toxic for 70kg person

Fluoride present in drinking water is 1mg per L.

So 200mg is present in 200L

200L of fluoridated drinking water is toxic to a 70kg person which  can cause death.

Using dimensional analysis,

drinking water (Answer)

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer

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