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3 years ago

a sample that has a half life of 45 years take ____ for the count rate to drop from 600 cpm to 150 cpm

Chemistry

1 answer:

Bond [772]3 years ago

5 0

Answer:

90yrs

Explanation:

Half life is the time taken for half of an original radioactive material to decay by half.

For the sample;

Half - life = 45yrs

Original amount = 600cpm

Start Number of atoms

0yrs 600cpm

First half life

45yrs 300cpm

Second half life

90yrs 150cpm

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Explanation:

Initial temperature of the water = $T_i=26.5^oC$

Final temperature of the water = $T_f=23.7^oC$

a) Change in temperature of the water,ΔT = $T_f-T_i$

$\Delta T=23.7^oC-26.5^oC=-2.8^oC$

Change in temperature of the water,ΔT is -2.8°°C.

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Exothermic reaction : Reaction in which heat released and the temperature if the surrounding is increased.

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1 mole of silver nitrate gives 1 mole of silver ion i.e. cation.

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0.05229 moles of cations are produced.

1 mole of silver nitrate gives 1 mole of nitrate ion i.e. anion .

Then 0.05229 moles of silver nitrate will give:

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3 years ago

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snow_tiger [21]

Answer:

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