1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ivahew [28]
3 years ago
11

You have 400 kg of a radioactive substance with a short half-life of 1000 years. how much will be left after these times?

Chemistry
1 answer:
Amiraneli [1.4K]3 years ago
8 0
Half-life of a radioactive substance is the time required to reduce the amount of substance to half of its initial amount. 

In present case, half-life is material is given as 1000 years and initial amount of material is given as 400 kg
 
Answer 1) Since, half-life of radio-active substance is 1000 years, therefore after 1st half life, amount of the material will be left to half the initial amount. Hence, amount of substance left after 1000 years = 400/2 = 200 kg.

Answer 2) For 2000 years, radioactive material has crossed 2 times the half life. Therefore ,  amount of the material will be left to 1/4 the initial amount. Hence, amount of substance left after 2000 years = 400/4 = 100 kg.

Answer 3) 
 For 4000 years, radioactive material has crossed 4 times the half life. Therefore , amount of the material will be left to 1/16 the initial amount. Hence, amount of substance left after 4000 years = 400/16 = 25 kg.
You might be interested in
What is the pressure in a 5.00 L tank with 49.00 grams of oxygen gas at 350 K? ___atm
ziro4ka [17]

Answer:

The right answer is "8.81 atm".

Explanation:

Given:

V = 5.00 L

Mass = 4900 g

MW = 32 g/mol

T = 350 K

Now,

Number of moles will be:

n = \frac{Mass}{MW}

   =\frac{49.00}{32}

   =1.53125 \ mole

By using the ideal gas equation, we get

⇒ PV=nRT

or,

⇒    P=\frac{nRT}{V}

By substituting the values, we get

           =\frac{1.53125\times 0.0821\times 350}{5.00}

           =\frac{44.1}{5.00}

           =8.81 \ atm  

4 0
3 years ago
The ability to put in a light bulb with greater ease is because the bottom half is what type of simple machine?
Travka [436]
A screw simple machine

4 0
3 years ago
An example of basic research is A) the development of new plastics that can be recycled. B) the study of the relationship betwee
elena-s [515]

Answer:

C) the study of the composition of the atom.

Explanation:

A research can be defined as a systematic investigation or careful consideration of study with respect to a particular problem using scientific methods such as collection of data, documenting critical information, analysis of data, and the establishment of facts in order to reach new conclusions.

Similarly, a basic research is an approach to research that's typically theoritical and it's aimed at developing a theory, searching for the truth or gain a better understanding about a phenomenon, subject, or basic laws on nature.

In this context, an example of basic research is the study of the composition of the atom.

An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such determines or defines the structure of a chemical element.

Generally, atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.

5 0
3 years ago
Please answer this I need it answered really soon thank you so much whoever answers this and I will give BRAINLIEST!!
max2010maxim [7]

Answer:

B extinction

Explanation:

as the species does not exist any more, the species is extinct, therefore making the pictured fossil of an extinct species

hope this helps

3 0
3 years ago
Read 2 more answers
Due to radioactive decay over many millions of years, it is possible for the element uranium to decay in
ruslelena [56]

The uranium within these items is radioactive and should be treated with care. Uranium's most stable isotope, uranium-238, has a half-life of about 4,468,000,000 years. It decays into thorium-234 through alpha decay or decays through spontaneous fission.

3 0
3 years ago
Other questions:
  • A compound has an empirical formula of C2H6. What additional piece of evidence is needed to determine the molecular formula?
    10·2 answers
  • PLEASE AWNSER THIS ASAP!!! 100points! i will give brainliest please awnser right!!!
    13·2 answers
  • How many moles of MgS2O3 are in 223 g of the compound
    7·2 answers
  • Answer these questions :) please
    8·1 answer
  • Which of the following electron configurations is correct?
    14·1 answer
  • . Consider the following 3 systems: a. A binary mixture with vapor-liquid equilibrium, both components are generally present in
    9·1 answer
  • Is is true or false that ocean currents affect the climate I certain regions on earth​
    7·2 answers
  • What is the name of GaF3?
    12·1 answer
  • What is true when a reaction has reached equilibrium?
    13·1 answer
  • Think and Discuss the changes you can do around you at home or in your school to help the
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!