Science MC exam T4

An isotope is

• 1. an atom with no charge

• 1. each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei

• 1. each of two or more forms of the same element that contain equal numbers of protons but different numbers of electrons around their nuclei.

• each of two or more forms of the same element that contain equal numbers of neutrons but different numbers of protons in their nuclei

An aluminium ion is represented by the symbol: Al³⁺.

The "3+" superscript tells us that this ion formed when a neutral aluminium atom:

• 1. lost one electron

• 1. lost two electrons

• 1. lost three electrons

• 1. gained three protons

• 1. gained two protons

Here are three isotopes of an element:   ¹²C        ¹³C         ¹⁴C

The element is: __________________

• 1. chlorine

• 1. copper

• 1. cobalt

• 1. carbon

Here are three isotopes of an element:   ¹²C       ¹³C      ¹⁴C
How many neutrons and electrons are in the third isotope? 

• 6, 8

• 14, 6

• 6, 6

• 8, 6

The diagram shows two isotopes of an element:   ¹

The number 6 refers to the _________________________

• 1. the number of electrons in the nucleus

• 1. the number of neutrons in the nucleus of the atom

• 1. the number of protons in the nucleus of the atom

• 1. the mass number of the atom

A radioisotope is

• 1. an unstable isotope of an element that emits radiation

• 1. a stable isotope of an element that does not emit radiation

• 1. is one that breaks down to release musical sounds

• 1. any isotope of an element

An electrically neutral atom of chlorine has an atomic number of 17 and a mass number of 37

In order, the number of protons, neutrons and electrons is:

• 1. 17, 20, 17

• 1. 17, 17, 17

• 1. 20, 17, 20

• 1. 20, 20, 17

Here are the three isotopes of Hydrogen:  
The number of nucleons (particles in the nucleus) for hydrogen-1, hydrogen-2 and hydrogen-3 are, respectively

• 1. 0, 1, 2

• 1. 1, 2, 3

• 1. 1, 1, 1

• 1. none of the above

Boron exists as two isotopes, boron-10 and boron-11.  Based on the atomic weight (10.81), which isotope should be more abundant

• 1. Boron-11

• there is not enough information to answer this question

• 1. Boron-10

• 1. They would be equally abundant

The 2011 Fukushima nuclear disaster released large quantities of radioactive isotopes into the environment. As part of the clean up effort, much of the contaminated material has been collected, and must be stored until it decays to safer radiation levels. One of the radioactive isotopes released, Cesium-137, has a half-life of 30 years. In what year will the remaining amount of Cesium-137 have reduced to approximately 10% of its initial amount?

• 1. 2021

• 1. 2500

• 1. 2110

• 1. 2041