Why do scientists sometimes discard theories?

The ph of a sodium acetate-acetic acid buffer is 4.70. calculate the ratio [ch3coo-] / [ch3cooh]

A piece of lithium metal is added to a beaker that contains water and phenolphthalein. Using what you know about the properties of bases, choose the best explanation for what you observe.

As magma cools and crystallizes minerals form is predictable patterns in a process known as

Both white phosphorus and red phosphorus are made up only of phosphorus atoms. Does this mean they are both pure substances? Could they be compounds?

The combustion of ethanol (C 2 H 6 O) produces carbon dioxide and water vapor. What equation best describes this process?

How do you balance __Mg + __HCl - - > __MgCl2 + ___ H2

How many grams of methane, CH4 are produced from the complete reaction of 5.15 moles of carbon monoxide, CO

If you change the state of something, say, liquid to solid, is it a physical or chemical change?

What type of calorimeter would be best to use if you wanted to measure the heat that is released when gasoline is burned?

Tina has a sample of gaseous water at a temperature of 400 C and a pressure of 4 atm. If Tina increases the pressure to 200 atm, will the gaseous water liquefy? Why or why not?