Chemistry Review

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

• Nitrogen(N)
• Sulfur(S)
• Arsenic (As)
• Silicon(Si)

For an investigation, a student measures the speed of a cart as it rolls down a ramp.  The student then records the data in the table.  Which of these best explains the student's data?

• The speed of the cart decreases as the cart rolls down the ramp because of friction between the cart and the ramp.
• The speed of the cart increases as the cart rolls down the ramp because the force acting on the cart is greater than the force of gravity.
• The speed of the cart increases as the cart rolls down the ramp because of forces acting on the cart are unbalanced.
• The speed of the cart decreases as the cart rolls down the ramp because of the forces acting on the cart are balanced.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-1

A scientist spilled a few drops of dilute hydrochloric acid on a lab table.  For safety purposes, the scientist sprinkled some baking soda onto the spill.  Which observation would provide the best evidence that a chemical reaction occurred?

• The baking soda and hydrochloric acid combined, and bubbles formed.
• The baking soda absorbed the hydrochloric acid.
• Some of the baking soda dissolved in the hydrochloric acid.
• The hydrochloric acid evaporated, leaving only the baking soda.

Tags

NGSS.MS-PS1-2

Four students raced toy cars on a track.  The mass and the acceleration of each car is recorded in the table.  Which toy car had the greatest applied force?

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS2-2

When trying to identify an unknown element, a scientist determines what other elements the unknown element reacts with chemically.  Which property of the unknown element determines the other elements it reacts with?

• The total number of neutrons in the unknown element
• The total number of particles in the nucleus of the unknown element
• The number of protons in the nucleus of the unknown element
• The number of valence electrons in the unknown element

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

An atom has 25 protons, 30 neutrons, and 25 electrons.  What is the charge of the atom's nucleus?

• +25
• +30
• -25
• -30

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

• 12
• 6
• 18
• 24

Tags

NGSS.MS-PS1-1

The chemical equation shown represents a reaction that produces fuel for certain cars.  Which substance represented in this equation is classified as an element?CO + H₂O --> CO₂  + H₂

• CO
• H₂O
• CO₂
• H₂

Tags

NGSS.MS-PS1-1

Many processes occur in the digestive system.  Which process is best classified as a physical change?

• Saliva converting the starch molecules in crackers into simple sugars
• Digestive enzymes breaking down proteins into smaller fragments
• Bacteria converting lactose into simple sugars in the intestines
• Teeth grinding an almond into smaller pieces in the mouth

Some students in a chemistry lab conducted an investigation in which they added four different solid substances to separate beakers of water.  They stirred the mixtures for one minute and then recorded their observations in the table.  Which substance most likely caused a new substance to be formed when mixed with water?

• Substance 1
• Substance 2
• Substance 3
• Substance 4

Tags

NGSS.MS-PS1-2