Solid aluminum is placed in a beaker with a blue solution of copper(II) nitrate. The resulting reaction causes the blue solution to turn colorless. The solid aluminum is consumed while a spongy, dark brown solid forms. Based on the observations listed above, which of the following inference(s) would be valid?

A. A synthesis reaction occurred.
B. A single replacement reaction occurred.
C. A double replacement reaction occurred.
D. A redox reaction occurred.

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?

These questions are based on the attached photo. the experiment is about burning magnesium metal with oxygen. 1. write the balanced chemical equation for the reaction you are performing. 2. calculate the mass of magnesium metal used in each trial. o trial 1: o trial 2: 3. calculate the actual yield of magnesium oxide for each trial. o trial 1: o trial 2: 4. magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. o trial 1: o trial 2: 5. determine the percent yield of mgo for your experiment for each trial. o trial 1: o trial 2: 6. determine the average percent yield of mgo for the two trials. your company currently uses a process with a similar cost of materials that has an average percent yield of 91 percent. if the average percent yield of this process is higher than that, this could save the company money. what is your recommendation to the company? support your recommendation using your data, calculations, and understanding of stoichiometry gathered from this lab.

What is the most common reason for matter changing its state?