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sdas [7]
3 years ago
14

The half life of a radioactive element is 2 million years. a mass of rock originally contained 200g of this element. how many gr

ams of the element are left after 4 million years?
Chemistry
1 answer:
julia-pushkina [17]3 years ago
8 0
Every 2 million years the amount is halved
0 million = 200g
2 million = 200g/2 = 100g
4 million = 100g/2 = 50g
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fomenos

Answer:

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Explanation:

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3 years ago
Read 2 more answers
For the reaction below, complete the rate expression that relates the change in concentration with respect to time to the rate o
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Answer: Rate in terms of disappearance of NO = -\frac{1d[NO]}{2dt}

Rate in terms of disappearance of Cl_2= -\frac{1d[Cl_2]}{1dt}

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Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

2NO+Cl_2\rightarrow 2NOCl

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Answer:

hey you wanna get it right try this one: 48.0 kcal

was released... at constant pressure.

Explanation:

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saw5 [17]

Answer:D. Compound.

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