Chemistry STAAR Review

A student places a piece of a potato into a container of hydrogen peroxide. One observation the student makes is that bubbles form around the potato. The presence of bubbles might indicate the formation of a new substance because bubbles - 

• could show that a gas is forming

• always rise to the top of a liquid. 

• are almost always perfectly spherical.

• usually burst after a few minutes.

Tags

NGSS.MS-PS1-2

Four students performed four different investigations by combining different substances. Their results are shown in the table provided. In which experiment are new substances being formed?

• Experiment 1

• Experiment 2

• Experiment 3

• Experiment 4

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

positive charge, found in nucleus, mass = one

• proton

• neutron

• electron

• ion

negative charge, found orbiting nucleus, mass is almost zero

• proton

• neutron

• electron

• ion

An atom of a certain element has 11 electrons, and a mass number of 23. This element is very reactive in room temperature. How many neutrons are in this atom?

• 11

• 12

• 33

• 23

Tags

NGSS.MS-PS1-1

An atom of which element has 37 protons, 48 neutrons and 1 valence electron?

• Neon (Ne)

• Carbon (C)

• Rubidium (Rb)

• Sodium (Na)

______ always gives the identify of the atom.

• Protons

• Neutrons

• Electrons

How many atoms of oxygen are in a molecule of glucose (C₆H₁₂O₆)?

• 4

• 6

• 12

• 24

Tags

NGSS.MS-PS1-1

Which of the models best represents CaCO₃?

• 
• 
• 
• 

Tags

NGSS.MS-PS1-1

How many elements are in C₆H₁₂O₆?

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1