Science Form 3 Chapter 7 Radioactivity

Who discovered polonium, the radioactive material?

• Wilhelm Roentgen

• Henri Becquerel

• Marie Curie

• Neil Bohr

The following radioactive radiation shall be transmitted when a radioactive material decay except

• Alpha particle

• Beta particle

• Gamma ray

• Cosmic ray

Which statement is true about radioactive decay?

• A random and non-spontaneous process

• A random and spontaneous process

• Stable nucleus become an unstable nucleus

• Does not emits radioactive radiation

Which of the following are units to measure radioactivity?

• Curie

• Becquerel

• Microsievert/hour

Which of the following device is used to measure the radiation dose?

• Ammeter

• Voltmeter

• Dosimeter

• Digital multimeter

What happen when a sodium atom becomes a sodium ion?

• Becomes a negative ion

• Number of protons become 10

• Becomes a positive ion

• The sodium atom received one electron

Which of the following is ionising radiation?

• Radio waves

• Infrared

• X-ray

• Microwaves

Which of the following is true about alpha particles?

• Deflected to positive plate

• High penetrating power

• High ionising power

• Cannot be stopped using paper

Radon-220 has a half-life of 56 s. Calculate the mass of radon-220 after 225 s if its original mass is 100 g ?

• 6.25 g

• 12.5 g

• 25 g

• 50 g

Select natural ionising radiation sources

• Cosmic rays

• Radioactive pollution

• Nuclear Weapon test

• Radon