5. Which of the following is NOT a physical change?

nailing together boards of wood

breaking an egg

dying your hair

adding food coloring to water

What amounts do you compare when determining whether a solution is dilute or concentrated?

How many atoms or molecules are in 5.0 moles of the following? a. O b. N c. MgCl₂ d. C₂H₃NO

You decide to make a salad for dinner. You have lettuce, tomatoes, olives, onions, cheese, and of course your favorite salad dressing. All the ingredients are in different ratios. A tossed salad is an example of what type of mixture?

Which of the following is an example of chemical energy changing into radiant energy

Which sample of matter has a crystal structure? (1) Hg (ℓ) (2) H2O (ℓ) (3) NaCl (s) (4) CH4 (g

Consider the following thermochemical equation: C (s) + O2 (g) → CO2 (g) ΔH = - 393 kJ CO (g) + ½O2 (g) → CO2 (g) ΔH =

Two colorless solutions are mixed together. Bubbles form as the solution is stirred. Give TWO possible explanations for this result.

What is a light-year? A. the distance light travels in one earth year B. the distance light travels from the sun to the earth C. the distance light travels in one orbit of the moon D. the time it takes light to travel across the universe

What's is a logical way that you could begin to investigate why your tire had low air pressure?

after balancing the redox equation FeCl3+Zn--->ZnCl2+Fe, what are the coefficients, in order from left to right?