How many variables should a scientist change at one time to have a good experiment?

A student has a solution with a pH of 7. The student adds HF, hydrogen floride, to the solution, hoping to increases the pH of the solution. What is wrong with this student's approach? Select one: A. You cannot change the pH of a solution. B.

Which changes of the state takes place when an igneous rock turns into sedimentary rock?

Which of the statements are evidence that gases do not always behave ideally? it is impossible to compress a gas enough so that it takes up no volume. when two gases are mixed, they follow dalton's law of partial pressures.

What is the volume of 52.3 grams of NO2 gas at stp

The combustion of a sample butane, C4H10 (lighter fluid) produced 2.46 grams of water. how much oxygen was used up in grams

How would each of the following procedural errors affect the results to be expected in this experiment? Give your reasoning in each case. (A) Not all of the liquid was vaporized when the flask was removed from the water bath.

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?

What is the mass (g) of 500. ml water if the density is 0.9901 g/ml?

Predict what the population of the United States will be in the year 2010

Assume we could alter the conditions in the duodenum. Which of the following would be consistent with inserting a large volume of highly acidic chyme which contained a large amount of fat?