OAP NSRL

What is radioactivity?

• A term that describes the forces that hold atomic nuclei together

• The movement of electrons around an atomic nucleus

• The application of heat energy to an atomic nucleus

• The emission of high-energy particles or waves from atoms

In beta decay, a(n) ___________ is emitted.

• gamma ray

• electron

• neutron

• helium particle

In gamma emission, ___________ is emitted.

• an electron

• a proton

• energy waves

• none of the above

Has a mass of 0 and a charge of 0

• Alpha
• Beta
• Gamma

Which of the following is a non-ionising radiation?

• X-ray

• Gamma Ray

• Microwave

• Beta Ray

If we start off with element ₂₄X⁵⁰ after an alpha decay we get another element Y that looks like

• ₂₂Y⁵⁰
• ₂₂Y⁴⁶
• ₂₀Y⁴⁸
• ₂₆Y⁵⁴

Which term best describes alpha particles?

• Deadly

• Harmless

• Scalding

• Dangerous

If the half-life of a radioactive substance is 4 days, how much of a 200-g radioactive sample is left after 16 days?

• 800g

• 50g

• 25g

• 12.5g

The three types of nuclear radiation in increasing order of penetrating power are ____.  

• alpha, beta, gamma 

• X ray, beta, gamma
• alpha, gamma, beta 
• X ray, gamma, beta 

Iodin-131 decays with half-life is 8 days to become Xenon-131. Calculate the mass of Iodin-131 after 24 days with a mass of 60g.

• 7.5 g

• 8.5 g

• 12.5 g

• 15.5 g