At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.  Ian sees an object with few colliding particles, and he compares it to another object with few colliding particles. Which is true about the objects the object with many colliding particles has a lower concentration of particles or the object with many colliding particles has a higher concentration of particles?
the object with many colliding particles has a lower concentration of particles


The more curved the surface of a lens is, the more it refracts the light that passes through it.  Terry had a glass lens that he made less curved over time. The lens now reflects more or less light?
less


Q: As animals grow their bones get longer and bigger, they grow more hair, and are able to take care of themselves by getting food, shelter, and water.  Scuffy was a puppy, and now he is a sick dog. Now that Scruffy is smaller, shorter, and balder than before, Scrufffy can take care of himself better or worse?
A: worse


Question: At higher elevations, there is less air to press on a given area.  Allen is riding his bike on a path. The course ends up 1000 feet lower above sea level compared to the beginning. At which point is the air resistance lower at the beginning or at the end?
Answer: at the beginning


*Question*
If blood volume in the body decreases, blood pressure decreases.  When there is more fluid in a tube the pressure in the tube increases or decreases?
**Answer**
increases


Q: Acids have pH values below 7. The lower the pH value, the more strongly acidic the substance.  You can find tables that show the pH value of different fruits and vegetables. The fruits such as apples are barely acidic so they have a pH value that is higher or lower?
A: higher