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

What is the approximate mass of 25 cm3 of silver, if the density is 10.5 g/cm3?

Use the following equation to answer the question below: Sb2S3 (s) + 3Fe (s) - - > 2Sb (s) + 3FeS (s) When 18.45g Sb2S3 reacts with an excess of Fe, 12.1g Sb is produced. What is the percent yield of this reaction? 65.6% 75.4% 84.1% 91.5%

Which of these is a compound? A. Steel B. Sugar C. Air D. Nitrogen

A variable is the factor in a controlled investigation that does not change. True or False

David says, "Pure honey has nothing else added." Susan says,"The honey is not really pure. It is mixture of many subsatnces. Who is right? Explain your answer.

How do guys Make sperm?

Maya's playroom is 12 m2. The length of the room is 3 m. What is the width? 4 m 8 m 15 m 36 m

How many moles of each element are in this sample p2o3

Does uranium or barium nucleus have a stronger net force holding its protons

Which statement correctly compares DNA and RNA? DNA is made up of a single strand, and RNA is made up of a double strand. DNA is made up of a double strand, and RNA is made up of a single strand. Both DNA and RNA are made up of a single strand.