9. A change in color when two solutions are mixed together is a clue that a

__has taken place.

A. chemical change

B. physical change

C. temperature change

D. change in state

What is the most commonly used word for the element

What is the empirical formula for a substance containing 37.5 grams of carbon, c, 12.5 grams of hydrogen, h, and 50.0 grams of oxygen, o?

A mixture contains 21.7 g NaCl, 3.74 g KCI, and 9.76 g Lici. How many moles of NaCl are in this mixture? (Molar Mass) NaCl: 58.44 g/mol KCI: 74.55 g/mol LiCl: 42.3

1. Describe a few of the properties of ozone and compare these to the properties of diatomic oxygen.

a student uses universal pH paper to find the pH of three solutions. solution A has a pH of 5 solution B has a pH of 11 and solution C has a pH of 7 identify which solution is acidic which solution is neutral and which solution is basic

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?

Aluminum oxide, Al2O3, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al2O3.

What volume of 2.00 m must be added to 150.0 ml of 1.00 m chloroacetic acid to produce a buffer solution having a ph of 3.30?