1. What is a semipermeable membrane? 2. Make a list of molecules that enters the cell by diffusion and another list for molecules that get out of the cell by the same diffusion process.
3. (Reflexive questions) Name 2 life process that needs diffusion to occurs. Explain it.

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

here's your answer.