8th Grade Science 1st Semester Test Review

How many atoms of oxygen are on the product side?

• 3

• 8

• 12

• 16

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-1

NGSS.MS-PS1-2

How many total atoms are in one formula unit of the compound FeC₅O₅?

• 5

• 11

• 15

• 26

Tags

NGSS.MS-PS1-1

How many atoms of sodium are included in one formula unit of the compound Na₂C₂O₄?

(a)  

Tags

NGSS.MS-PS1-1

A scientist studies the following chemical equation for the production of water. 2H₂ + O₂ → 2H₂O What happens to the mass of the reactants during this chemical reaction?

• mass of oxygen stays the same

• mass of hydrogen doubles

• mass of oxygen decreases

• mass of hydrogen increases

Tags

NGSS.MS-PS1-5

The conservation of matter can be demonstrated by using chemical equations. Which chemical equations do NOT follow the law of conservation of mass ? (There is more than 1)

• I₂ + 5Cl₂ + 6H₂O → 2HIO₃ + 10HCl

• Cl + 4Na → 4NaCl

• 4P + 5HNO₃ → 5NO + 3H₃PO₄

Tags

NGSS.MS-PS1-5

The picture shows a chemical reaction. According to the law of conservation of mass, what will be the mass (in grams) of water formed in the product? Enter your answer below. Enter only the number, not units.

(a)  

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

The force diagrams show different forces acting on five different boxes. How many boxes will experience motion?

• 0

• 2

• 3

• 4

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-1

The box is being pushed to the right with a force of 150 newtons, and to the left with a force of 300 newtons. What is the magnitude of the net force on the box?

(a)  

Tags

NGSS.MS-PS2-2

The rate of acceleration of an object is determined by the mass of the object and

• the initial velocity of the object.

• the forces acting on the object.

• the direction of movement of the object.

• the change in kinetic energy of the object.

Tags

NGSS.MS-PS2-2

A 50 N object is placed on a surface and starts to slide. What is the MOST likely reason the object begins to move?

• Gravity exerts a balanced force on the object.

• An unbalanced force causes acceleration.

• Friction is applied to the object.

• The forces acting on the object are in equilibrium.

Tags

NGSS.MS-PS2-2