RC #1: protons & val. electrons 8.5 B (thru 2023)

Two students make models of two elements and label them Element X and Element Y. Which statement is true about the two element's reactivity?

• Both are chemically reactive.

• Both are chemically nonreactive.

• Element X is more chemically reactive than Element Y.

• Element Y is more chemically reactive than Element X.

Tags

NGSS.MS-PS1-1

If element X is more reactive than element Y, which statement serves as evidence to support the answer to Part A?

• Both models show two shells surrounding the nucleus.

• Both models show ten neutrons in the nucleus.

• Element X has seven electrons in its outer shell.

• Element Y has an even number of protons and neutrons.

Tags

NGSS.MS-PS1-1

An atom would become a different element if which characteristic changed?

• The number of protons

• The number of neutrons

• The number of energy levels

• The number of valence electrons

Sodium and lithium have similar chemical properties. What characteristic of these elements explains why they are chemically similar?

• Their atoms both have one valence electron.

• Their atoms both have more neutrons than protons.

• Their atoms have the same number of energy levels.

• Their atoms contain equal numbers of protons and electrons.

A student prepared diagrams to model atoms of two elements. Atoms of which two elements are represented by these models?

• Oxygen, O, and neon, Ne

• Fluorine, F, and neon, Ne

• Silicon, Si, and phosphorus, P

• Beryllium, Be, and boron, B

Tags

NGSS.MS-PS1-1

Which pair of elements has reactivity that is similar to chlorine, Cl?

• Fluorine, F, and argon, Ar

• Fluorine, F, and iodine, I

• Sulfur, S, and bromine, Br

• Sulfur, S, and argon, Ar

Atoms of which two elements have a combined total of 23 protons?

• Sodium, Na, and magnesium, Mg

• Boron, B, and carbon, C

• Copper, Cu, and zinc, Zn

• None of these

In this model, which particle determines the reactivity of this atom?

• Particle W

• Particle X

• Particle Y

• Particle Z

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Based on these drawings, which element is the least reactive?

• Neon, because it has two energy levels with eight electrons in the second level

• Chlorine, because it has three energy levels with seven electrons in the third level

• Gallium, because it has four energy levels with three electrons in the fourth level

• Tin, because it has five energy levels with four electrons in the fifth level

Tags

NGSS.MS-PS1-1

Based on the information in the table, which conclusion about the chemical reactivity of these elements is valid?

• Boron is the most reactive because it has the most protons.

• Fluorine is the most reactive because it has 7 electrons in the outer shell.

• Silicon is the most reactive because it has an equal number of protons and neutrons.

• Gallium is the most reactive because it has many more neutrons than protons.

Tags

NGSS.MS-PS1-2