Unit 1 Practice test

(8.5A) What is the mass number of potassium (K) that has 20 neutrons?

• 18

• 19

• 20

• 39

(8.5A) In the early 1900’s many scientists thought that an atom consisted of a positive substance with negative charges scattered throughout the substance.  Then Ernest Rutherford completed an experiment that changed the concept of an atom.  His discovery led to the understanding that an atom consists mostly of empty space with – 

• protons orbiting a dense nucleus made of electrons and neutrons

• 1. electrons orbiting a dense nucleus made of protons and neutrons

• neutrons and protons orbiting a cloud of electrons

• 1. electrons and protons orbiting a cloud of neutrons

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NGSS.MS-PS1-1

 (8.5B) Tin (Sn) is a soft white metal.  It has a low melting point compared with other metals.  Tin is widely used as a coating for cans of food.  Which statement accurately describes atoms of tin?

• Tin atoms have 50 protons.

• Tin atoms have five valence electrons.

• Tin atoms have 119 neutrons.

• Tin atoms have 68 electrons.

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NGSS.MS-PS1-1

(8.5B) The atoms of a certain element each contain 11 protons and 1 valence electron.  Which statement correctly identifies this element and describes its chemical reactivity?

• 1. The element is sodium, and it is highly reactive.

• The element is fluorine, and is not very reactive.

• The element is sodium, and it is not very reactive.

• 1. The element is fluorine, and it is highly reactive.

 (8.5C)  A researcher wants to experiment with an element that reacts like phosphorus (P) but has a greater atomic mass.  Which element should the researcher select for the experiment?

• Nitrogen (N)

• Sulfur (S)

• Arsenic (As)

• Silicon (Si)

(8.5C) A student is studying the ways different elements are similar to one another. Diagrams of atoms from four different  elements are shown to the right.  Which two atoms are of elements in the same group in the periodic table?

• 1. atom 1 and atom 2

• 1. atom 1 and atom 4

• atom 2 and atom 3

• 1. atom 3 and atom 4

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NGSS.MS-PS1-1

(8.5A) Which of these best describes one of the two subatomic particles that  could be found at location X in the model of an atom shown to the right? 

• It has a mass but no charge.

• 1. It has no mass and a positive charge.

• 1. It has a large mass and a negative charge.

• 1. It has no mass and an equal number of positive and negative charges.

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NGSS.MS-PS1-1

(8.5A) A model of an atom is shown to the right.  An atom of which element is represented by this model?

• 1. Boron (B)

• 1. Carbon (C)

• 1. Neon (Ne)

• 1. Sodium (Na)

Tags

NGSS.MS-PS1-1

 (6.6A)  Aluminum, sulfur, and chlorine are elements found on the periodic table.  Tests involving these three elements would show that at normal room temperature – 

• 1. sulfur is malleable and aluminum conducts electricity

• 1. chlorine is malleable and conducts electricity

• 1. aluminum is malleable and conducts electricity

• 1. all three elements are malleable and conduct electricity.

 (8.5C)  The model of the periodic table below shows the locations of four elements. A student is asked to identify an element that is a pale-yellow brittle solid and does not conduct electricity.  At which location in this periodic table would the element most likely be found?

• 1

• 2

• 3

• 4