7th grade Science practice sheet

Question 1

Water is H₂O. What does the small 2 tell you?

• There are 2 hydrogen atoms for every oxygen atom
• There are 2 oxygen atoms
• There are 2 water molecules
• Hydrogen weighs 2 times as much as oxygen

Question 2

Which statement is true about the parts of an ecosystem?

• The non-living parts never change
• Only large animals affect other parts
• A change in one part can affect many other parts
• Each part acts on its own

Question 3

Grass stores 20,000 units of energy. About 10% of the energy at each feeding level is passed on to the next. How many units reach the frogs that eat the grasshoppers?

answer boxunits

Question 4

Put the stages of primary succession in order.

• 🌿Lichens and mosses grow
• 🌲A mature forest develops
• 🌾Soil builds up and grasses grow
• 🪨Bare rock

Question 5

Water as ice, as liquid water and as water vapor has the same kind of particle. What differs in each state?

• The number of different substances
• How the particles are arranged and how they move
• Whether the water is pure
• The kind of particle

Question 6

Which tubes in a stem carry water up from the roots?

• Petals
• Xylem
• Phloem
• Stomata

Question 7

A chemical reaction forms…

• only a new shape
• only a new state
• nothing new
• new substances

Question 8

Which process is very slow?

• A landslide
• A flash flood
• A volcanic eruption
• Mountains rising from plate collisions

Question 9

Why can't a magnet pick up aluminum cans?

• Aluminum is too heavy
• Aluminum isn't magnetic
• The cans are empty
• Magnets only attract plastic

Question 10

What is evaporation?

• A gas changing to a liquid
• A liquid changing to a gas
• A solid changing to a liquid