1. The movement of particles from a less crowded area to a more crowded area requires

a. sunlight

b. energy

c. a membrane

d. osmosis

2. What structures allow small particles to cross cell membrane

How is the way that a wind turbine works similar to the way that a hydroelectric plant works? How is it different?

A 0.75mol calcium carbonate (CaCO3) pellet has what mass?

Emerald-green crystals of the substance are used in nickel plating. what is the chemical name of this compound

Which term describes a pure substance that is made up of only one type of atom? 1) matter 2) rock 3) compound 4) element

Given the balanced equation below for the highly exothermic reaction of aluminum with oxygen to form aluminum oxide: What is the value of ΔH when 1.00 mol of aluminum reacts? What is the value of ΔH when 5.

c. When we heat water up by the Bunsen burner, what temperature is the boiling water? After 10 minutes

Assuming that air contains 78 percent N2, 21 percent O2 and 1 percent Ar, all by volume. How many molecules of each type of gas are present in 1.0 L of air at STP?

Two children are playing tag. Child A who is doing the chasing can run 100m in 24 seconds Child B is running away from child A and can run 64m in 21 seconds.

What ion does a base increase

What is the definition of Amplitude?