REVIEW: Matter & Energy

The best description for a compound is-

• two or more elements that are mixed together

• two or more elements that are chemically bonded

• a substance that contains only one type of atom

• a substance that is represented by a symbol

A student observed that sulfur (S) and bromine (Br) do not conduct electricity. He also observed that oxygen (O) and krypton (Kr) are gases at standard room conditions.

Which correct conclusion did the student reach about the elements?

• All four elements are metals.

• All four elements are nonmetals.

• Sulfur and bromine are metals, and oxygen and krypton are nonmetals.

• Sulfur and bromine are nonmetals, and oxygen and krypton are metals.

A neutral atom of sodium (Na) has an atomic number of 11 and a mass of about 23 amu.

Which of the four lists below shows the number of protons, neutrons, and electrons in the atom?

• p=12, n=11, e=12

• p=11, n=12, e=12

• p=23, n=11, e=23

• p=11, n=12, e=11

Tags

NGSS.MS-PS1-1

Nitrogen gas (N₂) reacts with hydrogen gas (H₂) to form ammonia (NH₃).

Which is a balanced equation that correctly represents this reaction?

• N₂ + H₂ --> NH₃

• N₂ + H₂ --> 2 NH₃

• N₂ + 2 H₂ --> 2 NH₂

• N₂ + 3 H₂ --> 2 NH₃

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which chemical equation correctly demonstrates the law of conservation of mass?

• CH₄ + 2 O₂ --> CO₂ + H₂O

• H₂O₂ --> 2 H₂O + O₂

• 2 Na + Cl₂ --> 2 NaCl

• 2 NH₄OH --> 2 NH₃ + H₂O

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student mixes two substances together in a flask. Which observation could indicate that a chemical reaction is taking place in the flask?

• The flask heats up.

• Bubbles of gas form in the flask.

• The contents change color.

• All of these

Tags

NGSS.MS-PS1-2

The shaded regions in the periodic table show four groupings of elements (A-D).

Which grouping includes mostly elements that do not react readily?

• Grouping A

• Grouping B

• Grouping C

• Grouping D

An ion has a charge of +1. Which list describes the possible total numbers of electrons, protons, and neutrons that the ion has?

(Think about the charges of each subatomic particle...)

• 1 proton, 0 neutrons, and 1 electron

• 1 proton, 0 neutrons, and 2 electrons

• 1 proton, 0 neutrons, and 0 electrons

• 2 protons, 1 neutron, and 2 electrons

Tags

NGSS.MS-PS1-1

A model of an atom is shown.

Which best describes the particles that make up the part labeled X in the model?

• They all have no charge.

• They all have a positive charge.

• Some have a positive charge and some have no charge.

• Some have a positive charge and some have a negative charge.

Tags

NGSS.MS-PS1-1

The chart gives the density of four metals.

A piece of an unknown metal has a volume of 5.0 cm³ and a mass of 35.6 g.

Which is a possible identify of the metal?

(Remember: Density = mass / volume)

• Aluminum

• Gold

• Lead

• Zinc

Tags

NGSS.MS-PS1-2