Radioactivity

Question 1

What are radioisotopes?

Answer 1

Radioactive isotopes of an element. Isotopes keep the same amount of protons and electrons but change in the amount of neutrons.

Question 2

How are radioisotopes used in cancer treatment?

Answer 2

They use a radioactive drug that seeks out and destroys cancer cells while minimising damage to neighbouring healthy cells.

Question 3

How are radioisotopes used in food preservation?

Answer 3

By reducing or eliminating microorganisms and insects.

Question 4

How are radioisotopes used in nuclear reactors?

Answer 4

Radioisotopes can sustain a controlled nuclear chain reaction (when one reaction causes additional reactions).

Question 5

Why are some isotopes radioactive and others not?

Answer 5

They could have an unbalenced number of neutrons,to many or to little, causing an unstable and therefore radioactive isotope

Question 6

Describe the characteristics of alpha particles, including penetrating power.

Answer 6

Alpha particles are relatively slow and heavy and can not penetrate skin. Postitivly charged

Question 7

Describe the characteristics of beta particles, including penetrating power.

Answer 7

Beta particles are small, fast-moving particles with a negative electrical charge, can not penetrate aluminium

Question 8

Describe the characteristics of gamma rays, including penetrating power.

Answer 8

Gamma rays are the smallest wavelengths and the most energy of any wave. No electrical charge, but is a photon.They can not penetrate masses of lead.

Question 9

Describe half life.

Answer 9

Half life is used to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive (the time required for a quantity to reduce to half of its initial value.)

Question 10

Define current.

Answer 10

The rate at which electrons flow. Symbol = I

Question 11

Define voltage.

Answer 11

The pressure from an electrical circuit’s power source that pushes charged electrons (current) through a conducting loop. Symbol = V

Question 12

Define resistance.

Answer 12

A measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms Symbol = Ω

Question 13

What is atomic number?

Answer 13

Number of protons

Question 14

What is atomic mass?

Answer 14

Number of protons + neutrons

Question 15

If an atom has 8 protons, how many electrons does it have?

Answer 15

8

Question 16

How does energy flow through ecosystems?

Answer 16

Primary producers use energy from the sun to produce their own food in the form of glucose, and then primary producers are eaten by primary consumers who are in turn eaten by secondary consumers, and so on

Question 17

Describe the water cycle.

Answer 17

Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow

Question 18

What are the basic compomets of the carbon cycle?

Answer 18

Photosynthesis, Decomposition, Respiration and Combustion. Carbon cycles from the atmosphere into plants and living things.

Question 19

What is the chemical equation for photosynthesis?

Answer 19

6CO2 + 6H2O = C6H12O6 . Water, sunlight and carbon dioxide turns into glucose and oxygen.

Question 20

Define the role of chlorophyll in photosynthesis.

Answer 20

Chlorophyll’s job in a plant is to absorb light—usually sunlight.

Question 21

What are the main processes of the carbon cycle?

Answer 21

PHOTOSYNTHESIS (Plants turning CO2 into organic carbon compounds, primarily glucose) AND RESPIRATION (All living organisms, including plants release carbon dioxide into the atmosphere when they respire) AND DECOMPOSITION (During decomposition, organic matter is broken down into simpler compounds, including CO2) AND COMBUSTION (When organic matter, such as fossil fuels (e.g., coal, oil, and natural gas), is burned for energy or during wildfires)

Question 22

Scientific Method

Answer 22

Change one thing
Measure something
Same, keep everything the same

Independant variable
Dependant Variable
Controls Variables

Question 23

vir pyramid

Answer 23

V = IxR
I=V÷R
R=V÷I

Question 24

What did Marrie Currie do?

Answer 24

Discovered radium and polonium. She is remembered her huge contribution to finding treatments for cancer.

Question 25

What did Sir Ernest Ruthford do?

Answer 25

Suggested the nuclear structure of the atom, discovered alpha and beta rays, and proposed the laws of radioactive decay.