What of the following is the BEST statement about dependent and independent variables? 1. A dependent variable is a factor that changes because of procedures conducted on the independent variable.
2. An experiment can have more than one of either kind of variable; you just have to keep your data straight.
3. An experiment can have several independent variables but only one dependent variable.
4. An independent variable is a factor that changes because of procedures conducted on the dependent variable

Answer asap need to be answered by wednesday morning explain how a buffer works, using an ethanoic acid / sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.

Achemical reaction is done in the setup shown, resulting in a change of mass. what will happen if the same reaction is done in a sealed container that is placed on the electronic balance?

The goal of this experiment was to answer the question "what is the effect of a gas' temperature on its volume? " you formulated the hypothesis below. hypothesis: if a fixed amount of gas is heated, then the volume will increase because the heat will cause the molecules of gas to move faster and further apart. to test this hypothesis, you changed the of the gas between 0 and 100°c (273 and 373 k) and calculated the resulting of the gas.